Category: Class 8

Students can Download English Lesson 1 Jim Corbett, A Hunter Turned Naturalist Questions and Answers, Summary, Activity, Notes, Samacheer Kalvi 8th English Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th English Solutions Term 1 Supplementary Chapter 1 Jim Corbett, A Hunter Turned Naturalist

A. Fill in the blanks.

1. Jim Corbett was born on _________
2. Corbett shot wild animals in his _________
3.  _________ was the first man-eater shot by Corbett.
4. Corbett shot the tigress dead, near the _________

Answer:

1. 25th July 1875
2. cine film camera
3. The Champawat Tiger
4. Chataar Bridge

B. Read the following passage and answer the questions given below.

Jim Corbett played a key role in establishing, India’s first national park in the Kumaon Hills, the Hailey National Park, in Uttarakhand, India. It was initially named after, Lord Malcolm Hailey. Jim Corbett died on 19 April 1955. The park was renamed in 1957 as, The Jim Corbett National Park. It was named after him to honour his role in establishing this protected area in 1930s.

Jim Corbett A Hunter Turned Naturalist Question 1.
Who played a key role in establishing the national park?
Answer:
Corbett played a key role in establishing the India’s first National Park in the Kumaon Hills.

Jim Corbett A Hunter Turned Naturalist Question And Answer Question 2.
Why was the park named Hailey National Park?
Answer:
The park was named ‘Hailey National Park’ to honour the Governor of United Provinces ‘Lord Malcolm Hailey’.

Jim Corbett A Hunter Turned Naturalist Summary Question 3.
When was it renamed as Jim Corbett National Park?
Answer:
The park was renamed in 1957 as the Jim Corbett National Park to honour his role in establishing the protected area in 1930s.

C. Answer the following in one or two words.

Jim Corbett Hunter Turned Naturalist Question 1.
What was the birth name of Jim Corbett?
Answer:
The birth name of Jim Corbett was Edward James Corbett.

Jim Corbett A Hunter Turned Naturalist 8th Std In Tamil Question 2.
What was the name of Corbett’s dog?
Answer:
The name of Jim Corbett’s dog was Robin.

Corbett Shot Wild Animals In His Answer Question 3.
How many kills did the Champawat Tiger recorded?
Answer:
The Champawat Tiger recorded 436 deaths in Nepal and the Kumaon area of India. Her attacks have been listed in the Guinness Book of World Records as the highest number of death from a tiger.

Jim Corbett Shot Wild Animals In His Question 4.
Who was the last kill of the Champawat Tiger?
Answer:
The last person to be killed by the Champawat Tiger was a 16 year old girl in a village near Champawat.

Jim Corbett A Hunter Turned Naturalist Book Back Answers Question 5.
When did Jim Corbett died?
Answer:
Jim Corbett died on 19th April 1955.

D. Answer the following in 100 words.

Jim Corbett Question Answer Question 1.
According to Corbett, why a tiger turns into a man eater?
Answer:
According to Corbett’s theory, a tiger starts eating humans, when they grow old or got hurt. As they cannot run fast, they start killing humans. People cannot run as fast . as animals. So they become easy prey. After eating human flesh once, a tiger will not
eat any other flesh. These tigers are called man-eaters. Join Corbett’s first man eating tiger hunt was the Champawat Tiger. It was a Bengal tigress. It was responsible for nearly 436 deaths in Nepal and the Kumaon area of India.

8th English Jim Corbett A Hunter Turned Naturalist Question 2.
How was the Champawat Tiger killed?
Answer:
Jim Corbett camped in the Kumaon District and started tracking the tigress. He moved around the villages and limited the activities of the man-eater. After several unsuccessful attempts, Corbett managed to kill the tiger. When a 16 year old girl was killed by the tigress, it left a trail of blood, which was followed by Jim. After a whole day of search, Jim, decided to organise a bait, the next day. With the help of the Thasildar of Champawat, the bait was organised with about 300 villagers. The next day, Corbett shot the tigress dead, near the Chataar Bridge in Champawat.

Question 3.
What were the findings of the postmortem ?
Answer:
A postmortem was done on the Bengal Tigress. It showed that the upper and lower ’ canine teeth on the right side of her mouth were broken. The upper one was broken in half and the lower one broke right down to the bone. This injury was a result of an old gunshot from the game hunter who failed to track and kill it. According to Jim Corbett this injury prevented her from hunting her natural prey and so she started to hunt humans.

Step To Success

Analogy – verbal reasoning questions.
There is certain relation between two given words, find the relation to find the missing word.

Question 1.
Reading : Knowledge, Work: ?
(a) Experience
(b) Engagement
(c) Experiment
(d) Employment
Answer:
(a) Experience

Question 2.
Cricket: Bat, Hokey: ?
(a) Field
(b) Stick
(c) Player
(d) Ball
Answer:
(b) Stick

Question 3.
Dog : Rabies, Mosquito : ?
(a) Plague
(b) Death
(c) Malaria
(d) Sting
Answer:
(c) Malaria

Question 4.
Man : Biography, Nation : ?
(a) Leader
(b) People
(c) Geography
(d) History
Answer:
(d) History

Question 5.
Bread: Bakery, Brick: ?
(a) Mint
(b) Kiln
(c) Furnace
(d) Mine
Answer:
(b) Kiln

Question 6.
Doctor: Diagnosis, Judge : ?
(a) Court
(b) Punishment
(c) Lawyer
(d) Judgement
Answer:
(d) Judgement

Connecting To Self

Try to know whether your hobby makes things easy.
Answer:

Jim Corbett, A Hunter Turned Naturalist Additional Questions

I. Choose the Correct Answers (MCQ).

Question 1.
Jim Corbett was a wildlife photographer
(a) American
(b) British
(c) German
(d) French
Answer:

Question 2.
Though he was an expert hunter, he admired
(a) game hunt
(b) birds
(c) wildlife
(d) travel
Answer:

Question 3.
He took no joy from the .
(a) kill
(b) chase
(c) deaths
(d) survival
Answer:
(d) kill

Question 4.
There she continued her killings in the district.
(a) Kumaon
(b) Wayanad
(c) Vadodara
(d) Kolar
Answer:
(a) Kumaon

Question 5.
The British government Jim Corbett to help the villagers.
(a) advised
(b) ordered
(c) commanded
(d) requested
Answer:
(d) requested

II. Identify the Character / Speaker.

1. “He had a lot of experience with tigers and other wild animals”.
2. “She was shot in 1907 by Jim Corbett”.
3. “He camped in the Kumaon district”.
4. “He took no joy from the kill”.
5. “All her kills happened during the daylight”.

Answer:

1. Jim Corbett
2. Bengal tigress
3. Jim Corbett
4. Jim Corbett
5. Bengal tigress

III. Write True or False against each statement.

1. Jim often hunted with his horse Robin.
2. The Bengal tigress was responsible for nearly 336 deaths in Nepal and Kumoan area.
3. The British government requested Jim Corbett to help the villagers.
4. Jim Corbett was always against game hunting.
5. People were not terrified to go out into the forest.

Answer:

1. False
2. False
3. True
4. True
5. False

IV. Very Short Questions with Answers.

Question 1.
What did Jim Corbett hunt?
Answer:
Jim Corbett hunted a number of man-eating tigers and leopards in India.

Question 2.
What did Jim admire?
Answer:
Corbett admired wildlife.

Question 3.
Did he kill wildlife for pleasure or sport?
Answer:
No, he did not kill wildlife for pleasure or sport.

Question 4.
When was the tiger shot?
Answer:
The tiger was shot in 1907 by Jim Corbett.

Question 5.
How old was the girl killed by the tiger?
Answer:
She was 16 years old.

V. Short Questions with Answers.

Question 1.
Where did the tiger begin her attacks?
Answer:
The tiger began her attacks in a Rupal village in western Nepal, Himalayas.

Question 2.
What did the Nepalese army do?
Answer:
The Nepalese army, after failing to kill the tiger, drove her across the border into India.

Question 3.
How were the people to go out and refused to leave?
Answer:
The people were terrified to go out and refused to leave their hunts for work after hearing the tigress’ roar from the forest.

Question 4.
According to Jim, what were the main cause of the mischief of wild animals?
Answer:
Deforestation and human encroachment were the main cause of the mischief of wild animals.

Question 5.
What did Jim educate the people?
Answer:
Jim went on lecturing tours to educate the people about their natural heritage and the need to conserve forests and their wildlife

VI. Paragraph Questions with Answers.

Question 1.
Describe the attacks of the Bengal tigress?
Answer:
The tigress began her attacks in a Rupal village in Western Nepal, Himalayas. Hunters were sent to kill the tiger, but she managed to escape from them. The Nepalese army failed to capture or kill the tigress. It drove the tigress across the border into India. There the tigress continued her killings in the Kumaon District. She killed the people mostly during the day time. After several incidents, people stopped going into the forest to collect firewood, fruits, roots and other things. They were terrified to go out, after hearing her roar from the forest.

VII. mind map

Question 1.

Answer:

1. killing humans
2. as animals
3. easy prey
4. a tiger
5. man-eaters

Question 2.

Answer:

1. The Champawat Tiger
2. Bengal Tigress
3. Guinness Book of World Records
4. fatalities
5. 1907

VIII. Rearrange the Jumbled Sentences.

A.

1. Jim Corbett died on 19th April 1955.
2. Jim played a key role in establishing India’s first national park in the Kumaon Hills.
3. It was named after him to honour his role in establishing this protected area in 1930s.
4. It was initially named after Lord Malcolm Hailey.
5. The park was renamed in 1957 as ‘The Jim Corbett National Park’.
Answer:
2,4,1, 5, 3
2. Jim played a key role in establishing India’s first national park in the Kumaon Hills.
4. It was initially named after Lord Malcolm Hailey.
1. Jim Corbett died on 19th April 1955.
5. The park was renamed in 1957 as ‘The Jim Corbett National Park’.
3. It was named after him to honour his role in establishing this protected area in 1930s.

IX. Read the passage and answer the questions.

A. Edward James Corbett, popularly known as Jim Corbett was a British wildlife photographer, hunter, tracker, naturalist, and writer. He has hunted a number of man-eating tigers and leopards in India. He had a lot of experience with tigers and other wild animals to shoot with his cine film ‘ camera.

Question 1.
Who was Jim Corbett?
Answer:
Jim Corbett was a wildlife photographer, hunter, tracker, naturalist and writer.

Question 2.
How did he shoot tigers and other wild animals?
Answer:
He shot the tigers and other wild animals with his cine film camera.

Question 3.
What was the name given to Jim by his parents?
Answer:
Jim was given the name ‘Edward James Corbett’ by his parents.

B. Jim Corbett was always against game hunting. He strongly advocated that deforestation and human encroachment were the main cause of the mischief of wild animals. He went on lecturing tours to educate the people about their natural heritage and the need to conserve forests and their wildlife.

Question 1.
Who was against game hunting?
Answer:
Jim Corbett was against game hunting.

Question 2.
According to Jim, what were the main cause of the mischief of wild animals?
Answer:
Deforestation and human encroachment were the main causes of mischief of wild animals.

Question 3.
What did Jim educate the people?
Answer:
Jim went on lecturing tours to educate the people about their natural heritage and the need to conserve wildlife.

Jim Corbett, A Hunter Turned Naturalist Additional Questions:

Jim Corbett was a British wildlife photographer, hunter, tracker, naturalist and writer. His birth name was Edward James Corbett. He had hunted a lot of man-eating tigers and leopards in India. He used to shoot the tigers and the wild animals with his cine film camera. His dog, Robin accompanied him for the hunt. Jim Corbett hunted these animals only to help the people and at the request of the government.

His first man-eating tiger hunt was ‘The Champawat Tiger’. It was a Bengal tigress which was responsible for nearly 436 deaths in Nepal and the Kumaon area of India. Her attacks have been listed in the Guinness Book of World Records as the highest number of deaths from a tiger. The tigress began her attacks in a Rupal village in Western Nepal, Himalayas. She continued her killings even in the Kumaon District. Hunters were sent to kill the tigress, but she managed to escape. People were frightened to go to the forest to collect firewood, fruits, roots and other things. Then the British government requested Jim Corbett to help the villagers.

He camped in the Kumaon District and started tracking the tigress. After several unsuccessful attempts, Corbett managed to kill the tigress. When it left a trail of blood, after killing a 16 year old girl, Corbett followed it. He organised a bait with about 300 villagers. The next day, he shot the tigress dead near the Chataar Bridge in Champawat in the year 1907.

Jim Corbett was always against game hunting. He promoted ‘The Association for the Preservation of Game” and the “All India conference for the Preservation of Wildlife”. He played a key role in establishing India’s first national park – ‘the Hailey National Park’. After Jim Corbett’s death on 19th April 1955, the park was renamed in 1957 as “The Jim Corbett National Park”.

Tamilnadu State Board New Syllabus Samacheer Kalvi 8th Tamil Book Solutions Guide Pdf Chapter 5.5 தொகைநிலை, தொகாநிலைத் தொடர்கள் Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 8th Tamil Solutions Chapter 5.5 தொகைநிலை, தொகாநிலைத் தொடர்கள்

கற்பவை கற்றபின்

Question 1.
பாடப்பகுதியில் இடம்பெற்றுள்ள தொகைநிலைத் தொடர், தொகாநிலைத் தொடர்களைக் கண்டறிந்து தனித்தனியே தொகுக்க.
Answer:
தொகைநிலைத் தொடர்கள்

தொகா நிலைத்தொடர்கள்

பாடநூல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக.

Question 1.
சொற்களுக்கு இடையே வேற்றுமை உருபு மறைந்து வருவது ……………………….
அ) வேற்றுமைத் தொகை
ஆ) உம்மைத் தொகை
இ) உவமைத் தொகை
ஈ) அன்மொழித் தொகை
Answer:
அ) வேற்றுமைத் தொகை

Question 2.
‘செம்மரம்’ என்னும் சொல் …………………. த்தொகை.
அ) வினை
ஆ) பண்பு
இ) அன்மொழி
ஈ) உம்மை
Answer:
ஆ) பண்பு

Question 3.
‘கண்ணா வா!’ – என்பது ……………….. த் தொடர்.
அ) எழுவாய்
ஆ) விளி
இ) வினைமுற்று
ஈ) வேற்றுமை
Answer:
ஆ) விளி

பொருத்துக

1. பெயரெச்சத் தொடர் – அ) கார்குழலி படித்தாள்.
2. வினையெச்சத் தொடர் – ஆ) புலவரே வருக.
3. வினைமுற்றுத் தொடர் – இ) பாடி முடித்தான்.
4. எழுவாய்த் தொடர் – ஈ) எழுதிய பாடல்.
5. விளித் தொடர் – உ) வென்றான் சோழன்.
Answer:
1. ஈ
2. இ
3. உ
4. அ
5. ஆ

சிறுவினா

Question 1.
தொகைநிலைத் தொடர்கள் எத்தனை வகைப்படும்? அவை யாவை?
Answer:
தொகைநிலைத் தொடர்கள் ஆறு வகைப்படும். அவையாவன:

• வேற்றுமைத்தொகை
• உவமைத்தொகை
• வினைத்தொகை
• உம்மைத்தொகை
• பண்புத்தொகை
• அன்மொழித்தொகை

Question 2.
இரவு பகல் என்பது எவ்வகைத் தொடர் என விளக்குக.
Answer:

• ‘இரவு பகல்’ இத்தொடர், ‘இரவும் பகலும்’ என விரிந்து பொருள் தருகின்றது.
• இதில் சொல்லின் இடையிலும் இறுதியிலும் `உம்’ என்னும் இடைச் சொல் மறைந்து நின்று பொருள் தருகிறது.
• இவ்வாறு சொற்களுக்கு இடையிலும் இறுதியிலும் ‘உம்’ என்னும் இடைச் சொல் மறைந்து நின்று பொருள் தருவதை உம்மைத்தொகை என்பர்.

Question 3.
அன்மொழித்தொகையை எடுத்துக்காட்டுடன் விளக்குக.
Answer:
வேற்றுமை, வினை, பண்பு, உவமை, உம்மை ஆகிய தொகைநிலைத் தொடர்களில் அவை அல்லாத வேறு பிற சொற்களும் மறைந்து வருவது அன்மொழித்தொகை எனப்படும்.

சான்று : பொற்றொடி வந்தாள்.

இத்தொடர் ‘பொன்னாலாகிய வளையலை அணிந்த பெண் வந்தாள்’ என்னும் பொருள் தருகிறது. இதில் ‘ஆல்’ என்னும் மூன்றாம் வேற்றுமை உருபும் ‘ஆகிய என்னும் அதன் பயனும் மறைந்து வந்துள்ளது. ‘வந்தாள்’ என்னும் சொல்லால் பெண் என்பதையும் குறிப்பதால், இது மூன்றாம் வேற்றுமைப் புறத்துப் பிறந்த அன்மொழித் தொகை ஆகும்.

மொழியை ஆள்வோம்

கீழ்க்காணும் தலைப்பில் இரண்டு நிமிடம் பேசுக.

1. கைத்தொழில் ஒன்றைக் கற்றுக்கொள்

பெருமை மிகுந்த சான்றோர் சபைக்கு என் முதற்கண் வணக்கத்தைத் தெரிவித்துக் கொள்கின்றேன். இப்பெருமைமிகு சபையில் நான் பேச எடுத்துக் கொண்ட தலைப்பு கைத்தொழில் ஒன்றைக் கற்றுக்கொள் என்பதாகும்.

ஏட்டுச் சுரைக்காய் கறிக்கு உதவாது’ என்பார்கள். அதைப்போல ஏட்டுப் படிப்பு படித்தவர்களுக்கு எந்த வேலையும் கிடைப்பதாகத் தெரியவில்லை.

படித்தாலும், படித்துப் பட்டம் பெற்றாலும் கைத்தொழில் ஒன்றையும் நாம் கூடவே, சேர்த்துக் கற்றுக்கொள்ள வேண்டும். படிப்புக்கேற்ற வேலை கிடைக்கும் வரை அந்த வேலைக்காகக் காத்திராமல் கற்ற கைத்தொழில் நமக்கு மிகவும் பயன்படும்.

தையல், ஓவியம், மரவேலை, மின்னணுச் சாதனங்கள் பழுதுபார்ப்பு, தட்டச்சு, கணிப்பொறி, கூடை பின்னுதல், அலங்காரப் பொருட்கள் செய்தல் இவற்றைப் பொழுதுபோக்கிற்காக நாம் பள்ளியில் கற்றாலும், அங்கு ஆழமாக ஆழ்ந்து கற்க வேண்டும். அதுவேதான், பிற்காலத்தில் படிப்புக்கு ஏற்ற வேலை கிடைக்கும் வரையில் நமக்கு நல்ல சம்பாத்தியத்தைக் கொடுக்கும்.

ஏட்டுக்கல்வி கைவிட்டாலும், கைத்தொழில் கல்வி உன்னைக் கைவிடாது என்பதைப் புரிந்து கொள்ள வேண்டும். எனவே, இளைஞர்களாகிய நாம் கைத்தொழில் ஒன்றைக் கற்றுக் கொள்ள வேண்டும் என்று சொல்லி என்னுடைய உரையை நிறைவு செய்கின்றேன்.

2. இதயம் கவரும் இசை

என்னை ஈன்ற தாய் மொழிக்கும், இந்தச் சான்றோர் பேரவைக்கும் முதற்கண் வணக்கத்தைத் தெரிவித்துக்கொண்டு, இதயம் கவரும் இசை என்ற நல்லதொரு தலைப்பில் சில நிமிடங்கள் பேசுகின்றேன். ஒவ்வொருநாளும் ஒவ்வொரு மனிதனுக்கும் ஒவ்வொரு பிரச்சினைகள் இருக்கத்தான் செய்கின்றன. துன்பங்கள் நம்மைத் துரத்தும் போது மன அமைதி தானாக தேடி வருவதில்லை . இசையின் பக்கம் நாம் தான் ஓடி வர – வேண்டும். புல்லாங்குழல் இசையும், வீணை இசையும், நாத முழக்கமும், மத்தளம் இசையும் மனதைப் பண்படுத்தும். இசைக்கச்சேரி கேட்கும் போது இதயமெல்லாம் மென்மையாகிவிடும்.

சங்க காலத்தில் தலைவன் ஒருவன் கள் உண்ட மயக்கத்தில் படுத்து கிடக்கின்றான். தொலைவில் தலைவிதினையைக் காயவைத்துக் கொண்டிருக்கின்றாள். தலைவன் படுத்து இருந்த இடத்தை நோக்கி மத யானை ஒன்று ஓடி வருகின்றது .ஐயோ! தலைவனுக்கு என்ன ஆகுமோ? என்று கவலைப்படாமல், தலைவி அருகிலிருந்த யாழை எடுத்து மீட்டினாள். மதம் பிடித்த யானை யாழ் இசையில் மயங்கி தலைவனை மிதிக்காமல் தெளிந்து சென்றதாம். இசை உயிரையும் காப்பாற்றும்.

குழந்தை பிறந்ததும் தாலாட்டி இசை செய்தான், அவன் வளர்ந்து திருமணம் ஆகும் போதும் மங்கள இசைதான். இப்படி இசை வாழ்வில் எத்தனையோ இடத்திலும் இடம் பெற்றிருக்கிறது. நம் வாழ்க்கையில் ‘இதயம் கவரும் இசை அனைவரையும் கவரும் தசை’ என்று சொல்லி என் உரையை நிறைவு செய்கிறேன்.

நன்றி! வணக்கம்!!

சொல்லக் கேட்டு எழுதுக.

முல்லை நில மக்களாகிய ஆயர்கள் குழல் ஊதுவதில் வல்லவர்கள். இதனைச் சம்பந்தர் திருப்பதிகத்தில் அமைந்த நிகழ்ச்சி ஒன்று விளக்குகிறது. திருவண்ணாமலைச் சாரலில் ஆயர் ஒருவர் ஆநிரைகளையும் எருமையினங்களையும் மேய்த்துக் கொண்டிருந்தார். மாலையில் அவற்றை எல்லாம் ஒன்று திரட்டினார்.

அப்போது எருமை ஒன்று காணாமல் போனதை அறிந்தார். தன் கையிலிருந்த குழலை எடுத்து இனிய இசையை எழுப்பினார். இன்னிசை கேட்ட எருமை அவரை வந்தடைந்தது. இவ்வாறு ஆயர்களின் இசைத் திறத்தைத் திருப்பதிகம் விளக்குகிறது.

கோடிட்ட இடங்களில் பொருத்தமான சொல்லுருபுகளை இட்டு நிரப்புக.

(கொண்டு, இருந்து, உடைய, காட்டிலும், ஆக, நின்று, உடன், விட, பொருட்டு)

1. இடி ………………….. மழை வந்தது.
2. மலர்விழி தேர்வின் …………………. ஆயத்தமானாள்.
3. அருவி மலையில் …………………. வீழ்ந்தது.
4. தமிழைக் ……………….. சுவையான மொழியுண்டோ !
5. யாழ், தமிழர் …………………….. இசைக் கருவிகளுள் ஒன்று.
Answer:
1. உடன்
2. பொருட்டு
3. இருந்து
4. காட்டிலும்
5. உடைய

பின்வரும் இசைக்கருவிகளின் பெயர்களை அகர வரிசைப்படுத்துக.

படகம், தவில், கணப்பறை, பேரியாழ், உறுமி, உடுக்கை, தவண்டை , பிடில், நாகசுவரம், மகுடி.
Answer:
உடுக்கை, உறுமி, கணப்பறை, தவண்டை , தவில், நாகசுவரம், படகம், பிடில், பேரியாழ், மகுடி.

பின்வரும் இணைச்சொற்களை வகைப்படுத்துக.

உற்றார் உறவினர், விருப்பு வெறுப்பு, காலைமாலை, கன்னங்கரேல், ஆடல்பாடல், வாடிவதங்கி, பட்டிதொட்டி, உள்ளும் புறமும், மேடுபள்ளம், நட்ட நடுவில்.

சரியான இணைச்சொற்களை இட்டு நிரப்புக.

(மேடுபள்ளம், ஈடுஇணை, கல்விகேள்வி, போற்றிப்புகழப்பட, வாழ்வு தாழ்வு, ஆடிஅசைந்து)

1. சான்றோர் எனப்படுபவர் …………………………. களில் சிறந்தவர் ஆவார்.
2. ஆற்று வெள்ளம் …………………… பாராமல் ஓடியது.
3. இசைக்கலைஞர்கள் …………………. வேண்டியவர்கள்.
4. தமிழ் இலக்கியங்களின் பெருமைக்கு …………………….. இல்லை.
5. திருவிழாவில் யானை ………………. வந்தது.
Answer:
1. கல்விகேள்வி
2. மேடுபள்ளம்
3. போற்றிப்புகழப்பட
4. ஈடுஇணை
5. ஆடி அசைந்து

கடிதம் எழுதுக

இருப்பிடச் சான்று வேண்டி வட்டாட்சியருக்கு விண்ணப்பம் எழுதுக.

அனுப்புநர்
சா. சுந்தர்,
த/பெ. ஆ. சங்கர்
34, குறிஞ்சி நகர்,
ஈரோடு – 638 001.

பெறுநர்
உயர்திரு. வட்டாட்சியர் அவர்கள்,
வட்டாட்சியர் அலுவலகம்,
ஈரோடு.

மதிப்புக்குரிய அய்யா,

பொருள் : இருப்பிடச் சான்றிதழ் வேண்டுதல் சார்பாக. வணக்கம்.

ஈரோடு, அரசு உயர்நிலைப் பள்ளியில் எட்டாம் வகுப்பு படிக்கின்றேன். 34, குறிஞ்சி நகர், ஈரோடு – 638 001 என்ற முகவரியில் பத்து ஆண்டுகளாக நாங்கள் வசித்து வருகின்றோம். அரசின் கல்வி உதவித்தொகைக்கு விண்ணப்பிக்க இருப்பிடச் சான்றிதழ் தேவைப்படுகின்றது. இத்துடன் குடும்ப அட்டை நகலும் ஆதார் அட்டை நகலும் இணைத்துள்ளேன். ஆகவே, எனக்கு இருப்பிடச் சான்றிதழ் வழங்கும்படி பணிவுடன் கேட்டுக் கொள்கிறேன்.

நன்றி!

இடம் : ஈரோடு
நாள் : 25.06.2020

இப்படிக்கு,
தங்கள் உண்மையுள்ள,
சா. சுந்தர்.

உறைமேல் முகவரி:
பெறுநர்
உயர்திரு. வட்டாட்சியர் அவர்கள்,
வட்டாட்சியர் அலுவலகம்,
ஈரோடு.

மொழியோடு விளையாடு

குறுக்கெழுத்துப்புதிர்.

இடமிருந்து வலம் :
1. முதற்கருவி எனப் பெயர் பெற்றது.
2. யாழிலிருந்து உருவான பிற்காலக் கருவி
7. இயற்கைக் கருவி
12. விலங்கின் உறுப்பைப் பெயராகக் கொண்ட கருவி

வலமிருந்து இடம் :
4. வட்டமான மணி போன்ற கருவி
8. ஐந்து வாய்களைக் கொண்ட கருவி
9. இசைக்கருவிகளை இசைத்துப் பாடல் பாடுவோர்

மேலிருந்து கீழ் :
1. 19 நரம்புகளைக் கொண்ட யாழ்
3. ஒன்றோடு ஒன்று மோதி இசைக்கப்படுபவை
5. சிறிய வகை உடுக்கை
6. பறை ஒரு ……………… கருவி

கீழிருந்து மேல் :
8. மூங்கிலால் செய்யப்படும் காற்றுக்கருவி
10. வீணையில் உள்ள நரம்புகளின் எண்ணிக்கை
11. திருமணத்தின்போது கொட்டும் முரசு

நிற்க அதற்குத் தக

என் பொறுப்புகள்:

1. கைவினைக்கலைகளுள் ஒன்றைக் கற்றுக்கொள்வேன்.
2. இசைக் கலையை வளர்த்த சான்றோர்களைப் பற்றி அறிந்து போற்றுவேன்.

கலைச்சொல் அறிவோம்

1. கைவினைப் பொருள்கள் – Crafts
2. புல்லாங்குழல் – Flute
3. முரசு – Drum .
4. கூடைமுடைதல் – Basketry
5. பின்னுதல் – Knitting
6. கொம்பு – Horn
7. கைவினைஞர் – Artisan
8. சடங்கு – Rite

இணையத்தில் காண்க

இசையின் வகைப்பாடுகள் பற்றிய செய்திகளை இணையத்தில் தேடி எழுதுக.

கூடுதல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக..

Question 1.
திருவாசகம் படித்தாள் – இதில் மறைந்து வரும் வேற்றுமை உருபு …………………..
அ) இரண்டாம் வேற்றுமை உருபு
ஆ) மூன்றாம் வேற்றுமை உருபு
இ) நான்காம் வேற்றுமை உருபு
ஈ) ஐந்தாம் வேற்றுமை உருபு
Answer:
அ) இரண்டாம் வேற்றுமை உருபு

Question 2.
கம்பர் பாடல் – இதில் இடம்பெற்றுள்ள வேற்றுமையுருபு ……………………
அ) கு
ஆ) இன்
இ) அது
ஈ) கண்
Answer:
இ) அது

Question 3.
காலம் கரந்த பெயரெச்சம் ………………..
அ) வினைத்தொகை
ஆ) பண்புத்தொகை
இ) வேற்றுமைத்தொகை
ஈ) உவமைத்தொகை
Answer:
அ) வினைத்தொகை

Question 4.
ஆடுகொடி, வளர்தமிழ் – ஆகியன …………………. க்குச் சான்றுகள்.
அ) வேற்றுமைத்தொகை
ஆ) உம்மைத்தொகை
இ) உவமைத்தொகை
ஈ) வினைத்தொகை
Answer:
ஈ) வினைத்தொகை

Question 5.
வெண்ணிலவு, கருங்குவளை ஆகியன ………………….. க்குச் சான்றுகளாகும்.
அ) வினைத்தொகை
ஆ) பண்புத்தொகை
இ) உவமைத்தொகை
ஈ) உம்மைத்தொகை
Answer:
ஆ) பண்புத்தொகை

Question 6.
இருபெயரொட்டு பண்புத்தொகைக்குச் சான்றாக அமையும் ஒன்றினைத் தேர்வு செய்க.
அ) மலர்விழி
ஆ) இரவுபகல்
இ) பொற்றொடி வந்தாள்
ஈ) பனைமரம்
Answer:
ஈ) பனைமரம்

Question 7.
இரவுபகல், தாய்தந்தை ஆகியன ………………………. க்குச் சான்றாகும்.
அ) அன்மொழித்தொகை
ஆ) உவமைத்தொகை
இ) உம்மைத்தொகை
ஈ) இருபெயரொட்டுப் பண்புத்தொகை
Answer:
இ) உம்மைத்தொகை

Question 8.
தொகாநிலைத் தொடர் வகைகள்
அ) 6
ஆ) 8
இ) 9
ஈ) 3
Answer:
இ) 9

Question 9.
எழுவாய்த் தொடர் அமையும் சான்றினைத் தேர்ந்தெடுக்க.
அ) மல்லிகை மலர்ந்தது
ஆ) நண்பா படி
இ) சென்றனர் வீரர்
ஈ) வரைந்த ஓவியம்
Answer:
அ) மல்லிகை மலர்ந்தது

Question 10.
‘நண்பா படி’ என்பது ……………………
அ) எழுவாய்த் தொடர்
ஆ) விளித் தொடர்
இ) வினைமுற்றுத்தொடர்
ஈ) பெயரெச்சத் தொடர்
Answer:
ஆ) விளித்தொடர்

குறுவினா

Question 1.
வேற்றுமைத் தொகை என்றால் என்ன? சான்று தருக.
Answer:

•  இருசொற்களுக்கு இடையில் வேற்றுமை உருபு மறைந்துவந்து பொருள் தந்தால், அதனை வேற்றுமைத் தொகை என்பர். 
• சான்று: திருவாசகம் (ஐ)படித்தான். (இரண்டாம் வேற்றுமைத் தொகை)

Question 2.
உருபும் பயனும் உடன்தொக்கத் தொகை என்றால் என்ன? சான்று தருக.
Answer:

• ஒரு தொடரில் வேற்றுமை உருபும் அதன் பொருளை விளக்கும் சொல்லும் மறைந்து வருவது உருபும் பயனும் உடன் தொக்கத் தொகை எனப்படும்.
• சான்று: பால் குடம்.
• பாலைக் கொண்ட குடம்’ இரண்டாம் வேற்றுமை உருபும் பயனும் உடன் தொக்கத் தொகை.

Question 3.
வினைத்தொகையை சான்றுடன் விளக்குக.
Answer:

• காலம் காட்டும் இடைநிலையும், பெயரெச்சவிகுதியும் மறைந்து வரும் பெயரெச்சம் வினைத்தொகை என்பர்.
• சான்று: வளர்தமிழ். இதில் காலம் காட்டும் இடைநிலைகள் தொக்கி வந்துள்ளன.
• வளர்ந்த தமிழ், வளர்கின்ற தமிழ், வளரும் தமிழ் எனவும் முக்காலத்திற்கும் பொருந்தும் படியாகப் பொருள் தருகின்றன. எனவே, இது வினைத்தொகை ஆகும்.

Question 4.
பண்புத்தொகை என்றால் என்ன? சான்று தருக.
Answer:

• பண்புப்பெயருக்கும் அது தழுவி நிற்கும் பெயர்ச்சொல்லுக்கும் இடையே ‘ஆன்’, ‘ஆகிய’ என்னும் பண்பு உருபுகள் மறைந்து வருவது பண்புத்தொகை எனப்படும்.
• சான்று: வெண்ணிலவு, கருங்குவளை.

Question 5.
‘மலர்விழி’ என்னும் சான்று அமையும் தொகை யாது? விளக்கு.
Answer:
‘மலர்விழி’ என்பது உவமைத்தொகை. மலர் போன்ற விழி என்ற பொருளைத் தருகிறது. ‘மலர்’ என்பது உவமை. ‘விழி’ என்பது உவமேயம். ‘போன்ற’ என்பது உவம உருபு. உவமைக்கும் உவமேயத்துக்கும் இடையில் உவம உருபு மறைந்து வந்தால் அது உவமைத்தொகை எனப்படும்.

Question 6.
எண்ணும்மை என்றால் என்ன? சான்று தருக.
Answer:
ஒன்றுக்கு மேற்பட்ட சொற்களில் ‘உம்’ என்னும் உருபு வெளிப்பட வருவது எண்ணும்மை ஆகும். சான்று: இரவும் பகலும், பசுவும் கன்றும்

சிறு வினா

Question 1.
தொகாநிலைத் தொடர் என்றால் என்ன? அதன் வகைகளை எழுதுக.
Answer:
(i) ஒரு தொடரில் இரு சொற்கள் வந்து அவற்றின் இடையில் சொல்லுருபு மறையாமல் நின்று பொருள் தந்தால் அதனை தொகாநிலைத்தொடர் என்பர்.

(ii) தொகாநிலைத்தொடர் ஒன்பது வகைப்படும். எழுவாய்த்தொடர், விளித்தொடர், வினைமுற்றுத் தொடர், பெயரெச்சத் தொடர், வினையெச்சத் தொடர், வேற்றுமைத் தொகாநிலைத் தொடர், இடைச்சொல் தொடர், உரிச்சொல் தொடர், அடுக்குத்தொடர்.

Tamilnadu State Board New Syllabus Samacheer Kalvi 8th Tamil Book Solutions Guide Pdf Chapter 5.3 நாட்டுப்புறக் கைவினைக் கலைகள் Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 8th Tamil Solutions Chapter 5.3 நாட்டுப்புறக் கைவினைக் கலைகள்

கற்பவை கற்றபின்

Question 1.
உங்கள் பகுதியில் கிடைக்கும் களிமண், பனையோலை போன்ற பொருள்களைப் பயன்படுத்திக் கைவினைப் பொருள்களைச் செய்து காட்சிப்படுத்துக.
Answer:

Question 2.
பனையோலையால் செய்யப்படும் பல்வேறு கைவினைப்பொருள்களின் படங்களைச் சேகரித்து படத்தொகுப்பு உருவாக்குக.
Answer:

பாடநூல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக.

Question 1.
பழந்தமிழ் இலக்கியங்களைப் பாதுகாத்து வைத்தவை ……………………
அ) கல்வெட்டுகள்
ஆ) செப்பேடுகள்
இ) பனையோலைகள்
ஈ) மண்பாண்டங்கள்
Answer:
இ) பனையோலைகள்

Question 2.
பானை ………………….. ஒரு சிறந்த கலையாகும்.
அ) செய்தல்
ஆ) வனைதல்
இ) முடைதல்
ஈ) சுடுதல்
Answer:
ஆ) வனைதல்

Question 3.
‘மட்டுமல்ல’ எனும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது ……………………
அ) மட்டு + மல்ல
ஆ) மட்டம் + அல்ல
இ) மட்டு + அல்ல
ஈ) மட்டும் + அல்ல
Answer:
ஈ) மட்டும்+அல்ல

Question 4.
கயிறு + கட்டில் என்பதனைச் சேர்த்தெழுதக் கிடைக்கும் சொல் …………………….
அ) கயிற்றுக்கட்டில்
ஆ) கயிர்க்கட்டில்
இ) கயிறுக்கட்டில்
ஈ) கயிற்றுகட்டில்
Answer:
அ) கயிற்றுக்கட்டில்

பின்வரும் சொற்களைச் சொற்றொடரில் அமைத்து எழுதுக.

1. முழுவதும் – பாடநூல் முழுவதும் வாசித்தால்தான் தெளிவு கிடைக்கும்.
2. மட்டுமல்லாமல் – ஏட்டுக் கல்வி மட்டுமல்லாமல் தொழில் கல்வியும் கற்க வேண்டும்.
3. அழகுக்காக – பல அரங்குகளில் சுடுமண் சிற்பங்களை அழகுக்காக வைத்திருப்பார்கள்.
4. முன்பெல்லாம் – முன்பெல்லாம் மண்பாண்டங்களை அதிகம் பயன்படுத்தினார்கள்.

குறுவினா

Question 1.
எவற்றையெல்லாம் கைவினைக்கலைகள் எனக் கூறுகிறோம்?
Answer:
மண் பொம்மைகள் செய்தல், மரப்பொம்மைகள் செய்தல், காகிதப்பொம்மைகள் செய்தல், தஞ்சாவூர்த்தட்டு செய்தல், சந்தன மாலையும் ஏலக்காய் மாலையும் செய்தல், மாட்டுக்கொம்பினால் கலைப் பொருட்கள் செய்தல் ஆகியவற்றை எல்லாம் கைவினைக் கலைகள் எனக் கூறுகிறோம்.

Question 2.
மண்பாண்டம், சுடுமண் சிற்பம் – ஒப்பிடுக.
Answer:

Question 3.
பனையோலையால் உருவாக்கப்படும் பொருள்கள் யாவை?
Answer:
குழந்தைகளுக்கான கிளுகிளுப்பை பொம்மைகள், பொருள்களை வைத்துக்கொள்ள உதவும் சிறிய கொட்டான், பெரிய கூடை, சுளகு, விசிறி, தொப்பி, ஓலைப்பாய், பனை மட்டை நாரிலிருந்து கயிறு, கட்டில், கூடை போன்றவை செய்யப்படுகின்றன.

சிறுவினா

Question 1.
பிரம்பினால் பொருள்கள் செய்யும் முறையைக் கூறுக.
Answer:
(i) பிரம்பு என்பது ஒரு தாவரம். முதலில் பிரம்புகளை நெருப்பில் காட்டிச் சூடுபடுத்த வேண்டும்.

(ii) சூடான பிரம்பை நட்டு வைத்திருக்கும் இரண்டு பாறைகளுக்கு இடையே செலுத்தி வளைக்க வேண்டும். அது வேண்டிய வடிவத்தில் கம்பி போல வளையும்.

(iii) பின்னர் அதனை தண்ணீரில் நனைத்து வைத்து விட்டால், அப்படியே நிலைத்து விடும். பிறகு அவற்றை இணைத்துச் சிறு ஆணிகளை அறைந்தும், சிறு பிரம்பு இழைகளைக் கொண்டும் தேவையான பொருட்களாக மாற்ற வேண்டும்.

Question 2.
மூங்கிலால் செய்யப்படும் பொருள்கள் குறித்து எழுதுக.
Answer:
மட்டக்கூடை, தட்டுக்கூடை, கொட்டுக்கூடை, முறம், ஏணி, சதுரத்தட்டி, கூரைத்தட்டி, தெருக்கூட்டும் துடைப்பம், மாடுகளுக்கான மூஞ்சிப்பெட்டி, பழக்கூடை, பூக்கூடை, பூத்தட்டு, கட்டில், புல்லாங்குழல், புட்டுக்குழாய், கால்நடைகளுக்கு மருந்து புகட்டும் குழாய், தொட்டில், பாடை ஆகியவை அனைத்தும் மூங்கிலால் செய்யப்படும் பொருள்கள் ஆகும்.

நெடுவினா

Question 1.
தமிழகக் கைவினைக் கலைகளைப் பற்றிய செய்திகளைத் தொகுத்து எழுதுக.
Answer:
மண்பாண்டக் கலை :

• குடம், தோண்டி, கலயம், கடம், மூடி, உழக்கு, அகல், உண்டியல், அடுப்பு, தொட்டி ஆகிய அனைத்துப் பொருட்களும் சுத்தமான களிமண்ணால் செய்யப்பட்டவை.
• பக்குவப்படுத்தப்பட்ட களிமண், மெல்லிய மணல் சாம்பல் ஆகியவற்றைக் கலந்து எடுத்துக் கொள்ள வேண்டும்.
• சக்கரத்தின் நடுவே வைத்து உரிய வடிவத்தால் அதைக் கொண்டு வர வேண்டும். பிறகு அடிப்பகுதியில் நூல் அல்லது ஊசியால் அறுத்து எடுத்து காயவைக்க வேண்டும். பிறகு உரிய மண்பாண்டம் தயாராகிவிடும்.
• மண்பாண்டங்களில் சமைத்த உணவு உடலுக்கு நல்லது.
• திருவிழாக் காலங்களிலும் சமயச் சடங்குகளிலும் மண்பானைகள் இன்றுவரை பயன்படுத்தப்பட்டு வருகின்றன.

மூங்கில் கலை :
(i) மூங்கில் கொண்டு பல கைவினைப் பொருட்கள் செய்யப்படுகின்றன.

(ii) மட்டக்கூடை, தட்டுக்கூடை, கொட்டுக்கூடை, முறம், ஏணி, சதுரத்தட்டி, கூரைத்தட்டி, தெருக்கூட்டும் துடைப்பம், மாடுகளுக்கான மூஞ்சிப்பெட்டி, பழக்கூடை, பூக்கூடை, பூத்தட்டு, கட்டில், புல்லாங்குழல், புட்டுக்குழாய், கால்நடைகளுக்கு மருந்து புகட்டும் குழாய், தொட்டில், பாடை ஆகிய அனைத்தும் மூங்கிலால் செய்யப்படும் பொருள்கள் ஆகும்.

(iii) முன்பு எல்லாம் திருமணத்தின் போது சீர்த்தட்டுகளாகப் பயன்படுத்தினர்

பனையோலைக் கலை :
(i) பனையோலையில் பல கைவினைப் பொருட்கள் உருவாக்கப்படுகின்றன.

(ii) குழந்தைகளுக்கான கிளுகிளுப்பை பொம்மைகள், பொருள்களை வைத்துக் கொள்ள உதவும் சிறிய கொட்டான், பெரிய கூடை, சுளகு, விசிறி, தொப்பி, ஓலைப்பாய், பனை மட்டை நாரிலிருந்து கயிறு, கட்டில், கூடை போன்றவை செய்யப்படுகின்றன.

பிரம்புக் கலை :
(i) பிரம்பு என்பது ஒரு தாவரம்.

(ii) முதலில் பிரம்புகளை நெருப்பில் காட்டி சூடுபடுத்த வேண்டும். சூடான பிரம்பை நட்டு வைத்திருக்கும் இரண்டு பாறைகளுக்கு இடையே செலுத்தி வளைக்க வேண்டும்.

(iii) அது வேண்டிய வடிவத்தில் கம்பி போல வளையும். பின்னர் அதனைத் தண்ணீரில் நனைத்து வைத்து விட்டால், அப்படியே நிலைத்து விடும். பிறகு அவற்றை இணைத்துச் சிறு ஆணிகளை அறைந்தும், சிறு பிரம்பு இழைகளைக் கொண்டு கூட்டியும் தேவையான பொருட்களாக மாற்ற வேண்டும்.

(iv) பிரம்பு மிகவும் குளிர்ச்சியானது. எனவே அதில் அமர்வது உடல்நலத்துக்கு நல்லது.
(v) மேலும் பிரம்புப்பொருள் வீட்டுக்கு அழகையும் கொடுக்கும்.

சிந்தனை வினா

Question 1.
கைவினைக் கலைகளுக்கும் சுற்றுச்சூழல் பாதுகாப்பிற்கும் இடையேயுள்ள தொடர்பு குறித்து எழுதுக.
Answer:
(i) கைவினைப் பொருட்கள் அனைத்தும் இயற்கையான பொருளால் தயாரிக்கப் படுபவை.

(ii) செயற்கையான பொருளோ தீங்கு விளைவிக்கும் இரசாயனமோ இதில் பயன்படுத்தப்படுவது இல்லை.

(iii) இயற்கையாகக் கிடைக்கும் களிமண், பனை ஓலை, மூங்கில், பிரம்பு ஆகியவற்றை முதன்மைப் பொருளாகக் கொண்டு கைவினைப் பொருட்கள் செய்யப்படுகின்றன.

(iv) கைவினைக் கலைகளுக்குப் பயன்படுத்தப்படக்கூடிய பொருட்களின் மீதத்தைப் பூமியில் புதைத்தாலும், அவை மக்கி விடும். இதனால் சுற்றுப்புறத்திற்கு எந்தத் தீங்கும் ஏற்படாது.

கூடுதல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக.

Question 1.
பானை ஓடுகள் கிடைத்துள்ள இடம் …………………..
அ) சிந்துசமவெளி
ஆ) ஆதிச்சநல்லூர்
இ) செம்பியன் கண்டியூர்
ஈ) கீழடி
Answer:
அ) சிந்துசமவெளி

Question 2.
முதுமக்கள் தாழிகள் கிடைத்துள்ள தமிழக இடம் ……………………..
அ) சிந்துசமவெளி
ஆ) ஆதிச்சநல்லூர்
இ) செம்பியன் கண்டியூர்
ஈ) கீழடி
Answer:
ஆ) ஆதிச்சநல்லூர்

Question 3.
மிகவும் பழமையான கைவினைக் கலைகளில் ஒன்று ………………….
அ) பிரம்புக் கலை
ஆ) மண்பாண்டக் கலை
இ) பனை ஓலைக்கலை
ஈ) மூங்கில் கலை
Answer:
ஆ) மண்பாண்டக் கலை

Question 4.
குளங்கள், ஆற்றங்கரைகள், வயல்வெளிகள் ஆகிய இடங்களில் கிடைக்கும் ……………………
அ) செம்மண்
ஆ) களிமண்
இ) வண்டல் மண்
ஈ) உவர்மன்
Answer:
ஆ) களிமண்

Question 5.
பானை செய்யும் சக்கரத்தின் வேறு பெயர் ………………..
அ) ஊசி
ஆ) நூல்
இ) திருவை
ஈ) சுழல்
Answer:
இ) திருவை

Question 6.
குழந்தைகளைப் படுக்க வைக்க உதவும் பாய் …………………..
அ) பந்திப்பாய்
ஆ) திண்ணைப் பாய்
இ) பட்டுப் பாய்
ஈ) தடுக்குப் பாய்
Answer:
ஈ) தடுக்குப் பாய்

Question 7.
உட்காரவும் படுக்கவும் உதவும் ………………… பாய்.
அ) பந்திப்பாய்
ஆ) திண்ணைப் பாய்
இ) பட்டுப் பாய்
ஈ) தடுக்குப் பாய்
Answer:
ஆ) திண்ணைப் பாய்

Question 8.
“முற்காலத்தில் பாய்மரக் கப்பல்களில் பயன்படுத்தியது கூட பாய் தான்” என்பதைக் கூறும் நூல் ………………….
அ) அகநானூறு
ஆ) பரிபாடல்
இ) புறநானூறு
இ) பதிற்றுப்பத்து
Answer:
இ) புறநானூறு

Question 9.
தமிழ்நாட்டின் மாநில மரம் ……………………
அ) தென்னை மரம்
ஆ) மாமரம்
இ) பனை மரம்
ஈ) மூங்கில் மரம்
Answer:
இ) பனை மரம்

Question 10.
பிரம்பு என்பது …………………. வகையைச் சேர்ந்த தாவரம்.
அ) செடி
ஆ) கொடி
இ) மரம்
ஈ) நீர்நிலை
Answer:
ஆ) கொடி

Question 11.
கலாமஸ் ரொடாங் என்னும் தாவரவியல் பெயர் கொண்டது …………………
அ) பிரம்பு
ஆ) மூங்கில்
இ) மண்பாண்டம்
ஈ) பனையோலை
Answer:
அ) பிரம்பு

குறுவினா

Question 1.
கைவினைக் கலைகள் என்றால் என்ன?
Answer:
அன்றாடப் பயன்பாட்டுக்காக அழகிய பொருள்களைத் தொழில் முறையில் உருவாக்கும் கலையைக் கைவினைக் கலை என்பர்.

Question 2.
மூங்கில் வகைகள் யாவை?
Answer:

• கல் மூங்கில்
• மலை மூங்கில்
• கூட்டு மூங்கில்

என மூங்கில் மூன்று வகைப்படும்.

Question 3.
கைவினைப் பொருட்கள் செய்யப் பயன்படும் மூங்கில் எவை?
Answer:
கூட்டு மூங்கிலே கைவினைப் பொருட்கள் செய்யப் பயன்படும் மூங்கில் ஆகும்.

Question 4.
மண்பாண்டப் பொருட்கள் யாவை?
Answer:
பானை, சட்டி, குடம், தோண்டி, கலயம், கடம், மூடி, உழக்கு, அகல், உண்டியல், அடுப்பு, தொட்டி ஆகியன மண்பாண்டப் பொருட்கள் ஆகும்.

Question 5.
களிமண் கிடைக்கும் இடங்கள் யாவை?
Answer:
குளங்கள், ஆற்றங்கரைகள் மற்றும் வயல்வெளிகள் ஆகியவற்றில் களிமண் கிடைக்கும்.

Question 6.
திருவை என்றால் என்ன?
Answer:
மண் பானை செய்யும் சக்கரத்தையே திருவை என்பர்.

Question 7.
மண்பாண்டங்களால் கிடைக்கும் நன்மைகள் யாவை?
Answer:

• மண்பாண்டங்களில் சமைத்த உணவு நல்ல சுவையுடன் இருக்கும்.
• மண்பாண்டத்தில் செய்யப்படும் உணவே உடல் நலத்திற்கும் நல்லது.
• மண் பானையில் வைத்த தண்ணீர் குளிர்ச்சியாக இருக்கும்.

Question 8.
சுடுமண் சிற்பங்கள் என்றால் என்ன?
Answer:
மண்பாண்டங்களைப் போன்றே களிமண்ணால் செய்யப்பட்டுச் சூளையில் சுட்டு எடுக்கப்படுபவை சுடுமண் சிற்பங்கள் ஆகும்.

Question 9.
பாயின் வகைகள் யாவை?
Answer:

• படுக்கும் பாய்
• பந்திப் பாய்
• திண்ணைப் பாய்
• பட்டுப்பாய்
• தொழுகைப் பாய்

Question 10.
பிரம்பு தருவிக்கப்படும் இடங்கள் யாவை?
Answer:
அஸ்ஸாம், அந்தமான், மலேசியா ஆகிய இடங்களில் இருந்து பிரம்பு தருவிக்கப் படுகிறது.

Question 11.
பிரம்புப் பொருட்களால் கிடைக்கும் நன்மைகள் யாவை?
Answer:

• பிரம்பு மிகவும் குளிர்ச்சியானது. எனவே, அதில் அமர்வது உடல்நலத்துக்கு நல்லது.
• மேலும், பிரம்புப் பொருள் வீட்டுக்கு அழகையும் கொடுக்கும்.

சிறுவினா

Question 1.
தமிழருக்கும் மண்பாண்டக் கலைக்கும் உள்ள தொடர்பைக் காட்டும் சான்றுகள் யாவை?
Answer:

• சிந்து சமவெளி அகழாய்வில் பானை ஓடுகள் கிடைத்துள்ளன.
• தமிழ்நாட்டில் ஆதிச்சநல்லூரில் முதுமக்கள் தாழிகள் கிடைத்துள்ளன.
• நாகை மாவட்டம் செம்பியன் கண்டியூரில் கலையழகு மிகுந்த மண்கலங்கள் கண்டுபிடிக்கப்பட்டுள்ளன.
• மதுரைக்கு அருகில் உள்ள கீழடியில் ஏராளமான சுடுமண் பொருட்கள் கிடைத்துள்ளன.
• இவையெல்லாம் தமிழருக்கும் மண்பாண்டக் கலைக்கும் உள்ள தொடர்பைக் காட்டும் சான்றுகளாகும்.

Question 2.
பாயின் வகைகளை விளக்குக.
Answer:

• குழந்தைகளைப் படுக்க வைப்பது தடுக்குப் பாய்.
• உட்கார்ந்து உண்ண உதவுவது பந்திப் பாய்.
• உட்காரவும் படிக்கவும் உதவுவது திண்ணைப் பாய்.
• திருமணத்துக்குப் பயன்படுவது பட்டுப் பாய்.
• இஸ்லாமியர் தொழுகைக்குப் பயன்படுத்துவது தொழுகைப் பாய்.

Question 3.
பாய்களில் எவையெவை இடம்பெற்றிருந்தன?
Answer:
(i) திருமணத்திற்குப் பயன்படுத்தும் பாய்களில் மணமக்கள் பெயர்கள் இடம் -5 பெற்றிருந்தன.

(ii) குத்துவிளக்கு, மயில், பூக்கள், வழிபாட்டுச் சின்னங்கள் ஆகியவையும் பாய்களில் இடம்பெற்றிருந்தன.

Question 4.
பிரம்பினால் செய்யப்பட்ட பலவகைப் பொருட்கள் யாவை?
Answer:

• கட்டில்
• ஊஞ்சல்
• நாற்காலி
• மேசை
•  பூக்கூடை
• பழக்கூடை
• இடியாப்பத் தட்டு
• அர்ச்சனைத் தட்டு
• வெற்றிலைப் பெட்டி

Students can Download Maths Chapter 1 Rational Numbers Ex 1.1 Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Maths Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Maths Solutions Term 1 Chapter 1 Rational Numbers Ex 1.1

8th Maths Exercise 1.1 Samacheer Kalvi Question 1.
Fill in the blanks:
(i) \(\frac{-19}{5}\) lies between the integers _____ and _____
(ii) The rational number that is represented by 0.44 is ______.
(iii) The standard form of \(\frac{+58}{-78}\) is _____.
(iv) The value of \(\frac{-5}{12}+\frac{7}{15}\) = ______
(v) The value of \(\left(\frac{-15}{23}\right) \div\left(\frac{+30}{-46}\right)\) is ______
Solution:
(i) -4 and -3
(ii) \(\frac{11}{25}\)
(iii) \(\frac{-29}{39}\)
(iv) \(\frac{1}{20}\)
(v) 1

8th Maths Exercise 1.1 In Tamil Question 2.
Say True or False.
(i) 0 is the smallest rational number.
(ii) There are an unlimited rationals between 0 and 1.
(iii) The rational number that does not have a reciprocal is 0.
(iv) The only rational number which is its own reciprocal is -1.
(v) The rational numbers that are equal to their additive inverses are 0 and -1.
Solution:
(i) False
(ii) True
(iii) True
(iv) False
(v) False

8th Maths Exercise 1.1 Question 3.
List five rational numbers between 2 and 0
(i) -2 and 0
(ii) \(\frac{-1}{2}\) and \(\frac{3}{5}\)
(iii) 0.25 and 0.35
(iv) -1.2 and -2.3
Solution:
(i) -2 and 0

Samacheer Kalvi 8th Maths Solutions Term 1 Pdf Question 4.
Write four rational numbers equivalent to -3 7
(i) \(\frac{-3}{5}\)
(ii) \(\frac{7}{-6}\)
(iii) \(\frac{8}{9}\)
Solution:

8th Standard Maths Exercise 1.1 Answers Question 5.
Draw the number line and represent the following rational numbers on it.

Solution:

8th Maths Book Example Sums Question 6.
Find the rational numbers for the points marked on the number line.

Solution:
(i) The number lies between -3 and -4. The unit part between -3 and -4 is divided into 3 equal parts and the second part is asked.
∴ The required number is \(-3 \frac{2}{3}=-\frac{11}{3}\).
(ii) The required number lies between 0 and -1. The unit part between 0 and -1 is divided into 5 equal parts, and the second part is taken.
∴The required number is \(-\frac{2}{5}\)
(iii) The required number lies between 1 and 2. The unit part between 1 and 2 is divided into 4 equal parts and the third part is taken.
∴ The required number is \(1 \frac{3}{4}=\frac{7}{4}\)

Samacheer Kalvi.Guru 8th Maths Question 7.
Using average, write 3 rational numbers between \(\frac{14}{5}\) and \(\frac{16}{3}\)
Solution:

Maths 8th Guide Samacheer Kalvi Question 8.
Verify that -(-x) is the same x for:
(i) x = \(\frac{11}{15}\)
(ii) x = \(\frac{-31}{45}\)
Solution:

Samacheer Kalvi 8th Maths Solutions Question 9.
Re-arrange suitable and add :
\(\frac{-3}{7}+\frac{5}{6}+\frac{4}{7}+\frac{1}{3}+\frac{13}{-6}\)
Solution:

8th Maths 1.1 Question 10.
What should be added to \(\frac{-8}{9}\) to get \(\frac{2}{5}\).
Solution:
Let the number to be added = x

8th Std Maths Exercise 1.1 Question 11.
Subtract \(\frac{-8}{44}\) from \(\frac{-17}{11}\)
Solution:

Maths Term 1 Question 12.
Evaluate:
(i) \(\frac{9}{2} \times \frac{-11}{3}\)
(ii) \(\frac{-7}{27} \times \frac{24}{-35}\)
Solution:

Maths 8th Class Chapter 1 Exercise 1.1 Question 13.
Divide
(i) \(\frac{-21}{5}\) by \(\frac{-7}{-10}\)
(ii) \(\frac{-3}{13}\) by -3
(iii) -2 by \(\frac{-6}{15}\)
Solution:

8th Maths In Tamil Question 14.
Simplify \(\left(\frac{2}{5}+\frac{3}{2}\right)+\frac{3}{10}\) as a rational number and show that it is between 6 and 7.
Solution:

8th Standard Maths Book Exercise 1.1 Question 15.
Write the five rational numbers which are less than -2.
Solution:
All the integers are rational numbers
∴ Rational numbers less than -2 are -10, -15, -20, -25, -30

8th Maths Guide Question 16.
Compare the following pairs of rational numbers

Solution:


\(\frac{10}{15}<\frac{12}{15}\)
∴ \(\frac{2}{3}<\frac{4}{5}\)

8th Maths Book Answer Question 17.
Arrange the following rational numbers is ascending and descending order.

Solution:

Objective Type Questions

8th Std Maths Guide Question 18.
The number which is subtracted from \(\frac{-6}{11}\) to get \(\frac{8}{9}\) is

Solution:
(B) \(\frac{-142}{99}\)
Hint:
Let x be the number be subtracted

Samacheer Kalvi Guru 8th Maths Book Solutions Question 19.
Which of the following rational numbers is the greatest?

Solution:
(A) \(\frac{-17}{24}\)
Hint:
LCM of 24, 16, 8, 32 = 8 × 2 × 3 × 2 = 96


∴ \(\frac{-17}{24}\) is the greatest number.

8th Std Maths Book Answers Question 20.
\(\frac{-5}{4}\) is a rational number which lies between
(A) 0 and \(\frac{-5}{4}\)
(B) -1 and 0
(C) -1 and -2
(D) -4 and -5
Solution:
(C) -1 and -2
Hint:
\(\frac{-5}{4}\) = \(-1 \frac{1}{4}\)
∴ \(\frac{-5}{4}\) lies between -1 and -2.

Samacheer Kalvi 8th Maths Book Question 21.
The standard form of \(\frac{3}{4}+\frac{5}{6}+\left(\frac{-7}{12}\right)\) is

Solution:
(D) 1
Hint:

8th Maths Book Samacheer Kalvi Question 22.
The sum of the digits of the denominator in the simplest form of \(\frac{112}{528}\)
(A) 4
(B) 5
(C) 6
(D) 7
Solution:
(C) 6
Hint:

Sum of digits in the denominator = 3 + 3 = 6

Question 23.
The rational number (numbers) which has (have) additive inverses is (are)
(A) 7
(B) \(\frac{-5}{7}\)
(C) 0
(D) all of these
Solution:
(D) all of these
Hint:
Additive inverse of 7 is -7
Additive inverse of \(\frac{-5}{7}\) is \(\frac{-5}{7}\)
Additive inverse of 0 is 0.

Question 24.
Which of the following pairs is equivalent?

Solution:
(B) \(\frac{16}{-30}, \frac{-8}{15}\)
Hint:

∴ \(\frac{16}{-30}\) and \(\frac{8}{15}\) are equivalent fraction.

Question 25.
\(\frac{3}{4} \div\left(\frac{5}{8}+\frac{1}{2}\right)\) =

Solution:
(C) \(\frac{2}{3}\)
Hint:

Students can Download English Lesson 2 Cyber Safety Questions and Answers, Summary, Activity, Notes, Samacheer Kalvi 8th English Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th English Solutions Term 3 Prose Chapter 2 Cyber Safety

Read And Understand

A. Say true or false.

1. Gladin’s mom knew how screw guage works.
2. We use internet to gather information and gain knowledge.
3. Rani was frightened of an online predator.
4. Strangers don’t misuse your information.
5. Do not give your name, address, telephone number to the strangers.
6. Too much of anything is good.

Answer:

1. False
2. True
3. True
4. False
5. True
6. False

B. Answer the following questions in a sentence or two.

Cyber Safety 8th Standard Question 1.
Why did Gladin’s mom ask him to browse?
Answer:
Gladin’s mom asked Gladin to browse to know about the working of a screw gauge.

Cyber Safety 8th Standard Summary Question 2.
Why do we use internet?
Answer:
We use internet to gather information and gain knowledge.

8th Standard English Cyber Safety Question 3.
What was Rani afraid of?
Answer:
Rani was afraid of a stranger chatting with her everyday, using bad words.

Cyber Safety Questions And Answers Class 8 Question 4.
What was father’s advice to Rani?
Answer:
Her father advised Rani not to respond to the stranger’s message.

Cyber Safety Book Back Answers Question 5.
Who is an online predator?
Answer:
An online predator is a person who sexually exploits a child over the internet.

Cyber Safety Class 8 Question 6.
What was father’s instruction to Gladin and Rani?
Answer:
He instructed them never to chat with any unknown person. Never to share their personal details with any stranger.

Cyber Safety Summary Question 7.
What do strangers do with our personal information?
Answer:
The strangers may use our profile and misuse our information, without our knowledge.

8th English Cyber Safety Question 8.
What are the benefits of computer?
Answer:
The computer connects us to the internet, helps us to learn and keeps us informed. It saves time, improves our ability and keeps us entertained.

C. Answer the following in about 100 words.

Cyber Safety Questions And Answers Question 1.
How should one use the technology of the present world?
Answer:
One should use the technology of the present world carefully and wisely It is beneficial to all of us. But we face some negative effects, while using it Online facilities are for sharing information or knowledge among known members. We should never chat with anybody, until we know them. They could be our classmates, friends and family members, we should keep our personal details very private. Strangers may use our profile and misuse our information without our knowledge. Internet or mobile helps us to connect with people around the world. They allow us to watch various.activities. But too much of anything is not good for us.

Cyber Safety Samacheer Kalvi Question 2.
What happens if someone is addicted to mobile phone?
Answer:
Mobile phones help us to get connected with the people around us. They allow us to watch movies, listen to music, play games and enjoy various other activities. But there is a chance to get addicted to this power house of entertainment. Mobile addiction causes several serious problems such as headache, weekend eyesight and sleep disorders. We also get depressed and have a stressed life. Problems like social isolation, aggressive behavior, financial problems and ruined relationship are also . caused. Our profession is also affected by the addiction of mobiles.

Cyber Safety Prose Summary Question 3.
“We can’t ignore the benefits of internet and mobile phone” Justify.
Answer:
We can’t ignore the benefits of internet and mobile phones to our life, educationally and socially. They help us to connect with people around the world. They allow us to watch movies, listen to music, play games and enjoy various other activities.

Internet helps us to gather information and gain knowledge, Online facilities are for sharing knowledge and information among known members. We should never chat with anybody until we know them like classmates, friends and family members. We should also limit the usage of internet and mobile phone to take charge of our lives.

Vocabulary

British And American English

D. Find the suitable British or American English word and fill in the following.
Answer:

Spelling Differences

E. Find the suitable British or American English spelling and fill in the following.
Answer:

Listening

F. Complete the following statements appropriately:

Mobile Phones: Uses and Abuses

The invention of mobiles phones is a great achievement and plays an important part in our daily life. Most of us nowadays carry the world in our pocket! It is amazing but true. A mobile phone can make us connected to the rest of the world within a second. Today, mothers do not have to tension if then sons ox daughters axe fate, businessmen do not have to queue up before a telephone booth to make an important call. Apart from making calls and sending SMS, the mobile phone is used as a multipurpose gadget. It is a calculator, timepiece, calendar, voice recorder, media player, camera, gaming device, net browser and what not. Its development brought convenience and advantages to the world. Communication between people has become quite easy and very fast. We can keep in contact with others from any place on the bus, in a street or in a meeting by sending a message for less than the price of a call. The Internet can be accessed through it and it is also used to click photos and shoot videos.

Though the mobile phone is a giant step of technological advancement, its abuses cannot at all be overlooked. Talking or texting while driving may lead to accidents. Students misuse this . tool in various ways and give way to social pollution. Its many aspects are beneficial but some are negative effects as well. The radiations of mobile may be dangerous to health and may cause a headache, ear ache and blurring vision. These invisible radiations destroy the cells located in ear and head which cause damage to the brain and nephrons in the head region. Its use in certain places causes disturbance sometimes, such as in a classroom etc. Mobile phones with camera are causing – privacy problems such as using it as a hidden camera to take pictures and making videos.

1. A mobile phone is like a world in our pockets as it is amazing.
2. Parents do not have to remain in tension if their sons and daughters are late because mobile phones can make us connected to the rest of the world within a second.
3. Some of the negative effects of a mobile phone are:
   • headache
   • ear ache
   • blurring vision
   • radiations destroy cells in ear and head
4. Excessive use of mobile phones can be hazardous to ones health as it has negative effects.
5. A mobile phone is a threat to ones privacy as using it as a hidden camera to take picture and making videos.

Speaking

G. Imagine a world with no books, but only e-books. How would you find such a world? Deliver a two-minute talk.
Answer:
Good Morning Friends,

Let us think of a world without books. If we live in a world of e-books, how will we find such a world? There’s no need to come to school, have teachers to teach us and there will be no punishment from our teachers. It’s wonderful! Isn’t it? E-books take up less space. You can store hundreds and thousands of E-books on your computer or reading device. They are portable. With today’s technology, you can read E-books everywhere, without worrying about their weight. They can show links, for easy access to more information and related websites.

E-books can be interactive. They contain audio, video and animations. These can enhance the message that the author is trying to convey. They also serve an important purpose in the online world from different perspectives. Smart phones, tablets, e-readers, as well as laptops and desktops can access an e-book. So let’s together opt for the wonderful world of e-books and enjoy our life. Thank you.

Writing

H. Write a character sketch of any character from fiction that has made an impact on you.
Answer:
Character sketch of Sherlock Holmes :
The best character that had made an impact on me from fiction was “Sherlock Holmes”.
He is an extraordinary personality and a modern hero. The dressing gown, loose coat,
hips and his investigation skills are the things that come to my mind, when I think about him. His high intelligence and his creative imagination are his best traits. His workaholic nature is one of his best qualities. Sherlock Holmes character was created by the Scottish writer “Arthur Conan Doyle”. He is a detective who tries to find out who committed crimes. In the story “The Adventure of the Speckled Band”, Helen Stoners twin sister, Julia dies from an unknown cause, shortly before being married. Helen takes this case to Sherlock Holmes. Using his powers of observation, intelligence and perseverance, Holmes races to find the murderer. So this character had an immense impact on me.

Grammar

Sentences : Simple, Compound, And Complex

A. State which of the following sentences are Compound,

1. Man proposes, but God disposes.
2. I went because I was invited.
3. Jancy returned home because she was tired.
4. Whatever you do, do well.
5. Listen carefully and take notes.
6. I called him, but he gave me no answer.
7. The town in which I live is very large.
8. They always talk who never think.
9. We must eat to live, but we should not live to eat.
10. Govern your passions or they will govern you.

Answer:

1. Compound sentence
2. Compound sentence
3. Compound sentence
4. Complex sentence.
5. Compound sentence
6. Compound sentence
7. Complex sentence.
8. Complex sentence.
9. Compound sentence
10. Compound sentence

Tense – Time

B. Fill in the blanks with appropriate form of the verbs given in the brackets.

1. When the burglars broke into the house, everybody _________ sound sleep, (have)
2. The milk _________ over as she went to see the crowd passing by with loud slogans, (spill)
3. If Karthik _________ any mistake, he will be rewarded, (not + make)
4. They were watching TV when they _________ a loud bang at the door, (hear)
5. The _________ bus the stop before we could catch it. (leave)
6. Ashok _________ the same song for last three days. It has become boring now. (play)
7. Manju _________ after we reach home, (call)
8. The show _________ its one thousand episodes by next month, (complete)
9. Don’t worry, we will be _________ the airport in time, (reach).
10. Danial has _________ sick after eating some snacks at the street side shop, (fall)

Answer:

1. was having a
2. was spitting
3. did not make
4. heard
5. left
6. had been playing
7. called
8. will have been completed
9. reaching
10. fallen

C. Tick the correct option to complete the sentences.

8th Cyber Safety Question 1.
The climate of the city _________ mild and pleasant most of the time.
(a) is remaining
(b) remains
(c) was remaining
(d) is remained
Answer:
(b) remains

Cyber Safety Question Answer Question 2.
One day he _________ into a hotel in Ooty, a beautiful city in Tamilnadu.
(a) booking
(b) was booking
(c) booked
(d) had booked
Answer:
(c) booked

Cyber Safety Summary 8th Standard Question 3.
You will certainly _________ rewards for what you are doing.
(a) getting
(b) had got
(c) was getting
(d) be-getting
Answer:
(d) be getting

Samacheer Kalvi 8th English Book Solutions Question 4.
Do you _________ the day we moved the piano upstairs?
(a) remember
(b) remembered
(c) are remembering
(d) had remembered
Answer:
(a) remember

8th English Guide Cyber Safety Question 5.
The rain completely _________ our day.
(a) spoilt
(b) is spoiling
(c) is spoilt
(d) was spoilt
Answer:
(a) spoilt

Question 6.
Akbar _________ the king at the age of fifteen after the sudden death of his father.
(a) was becoming
(b) had become
(c) became
(d) become
Answer:
(c) became

Question 7.
The criminal _________ the place before the police could reach.
(a) was escaping
(b) had escaped
(c) is escaping
(d) will escape
Answer:
(b) had escaped

Question 8.
They _________ all the arrangements before the guest’s is arrival.
(a) will have made
(b) will be made
(c) had been making
(d) were making
Answer:
(a) will have made

Question 9.
Sabithra _________ her job by tomorrow evening.
(a) will be completing
(b) will complete
(c) will have completed
(d) will have been completing
Answer:
(d) will have been completing

Question 10.
Harshini _________ her mother in making rangoli in the yard for last one hour.
(a) is helping
(b) has helped
(c) has been helping
(d) helps
Answer:
(c) has been helping

D. Identify the errors in the sentences given below and rewrite them.

Question 1.
These grapes are tasting sour.
Answer:
These grapes taste sour.

Question 2.
I am thinking you are wrong.
Answer:
I think you are wrong.

Question 3.
She is seeming sad.
Answer:
She seems sad.

Question 4.
He is having a cellular phone.
Answer:
He has a cellular phone.

Question 5.
She watched TV when her husband came.
Answer:
She was watching TV, when her husband came.

Cyber Safety Additional Questions

I. Choose the correct synonyms for the italicized words.

Question 1.
Let us browse about it
(a) download
(b) scan
(c) upload
(d) type
Answer:
(b) scan

Question 2.
Rani seems like she is frightened of something.
(a) scared
(b) worried
(c) bold
(d) happy
Answer:
(a) scared

Question 3.
Still if he bothers you, I will take care of him.
(a) continues
(b) entertains
(c) disturbs
(d) avoids
Answer:
(c) disturbs

Question 4.
Keep your personal details very private.
(a) public
(b) general
(c) common
(d) private
Answer:
(d) private

Question 5.
Strangers may misuse your information.
(a) use wrongly
(b) misapply
(c) utilize
(d) use
Answer:
(b) misapply

Question 6.
There is a chance to get addicted to this power house of entertainment.
(a) indifferent
(b) dependent
(c) disliked
(d) disgusted
Answer:
(b) dependent

Question 7.
We can’t ignore the beneficial of internet.
(a) acknowledge
(b) remember
(c) watch
(d) neglect
Answer:
(d) neglect

Question 8.
Are you suspecting any Online predator?
(a) trusting
(b) believing
(c) doubting
(d) unsuspecting
Answer:
(c) doubting

II. Choose the correct antonyms for the italicized words.

Question 1.
Too much of anything is goood for nothing.
(a) nobody
(b) everything
(c) none
(d) nothingness
Answer:
(b) everything

Question 2.
But we must limit their usage to take charge of our lives.
(a) maximum
(b) broader
(c) increase
(d) contract
Answer:
(b) broader

Question 3.
Mobile addiction causes several serious problems.
(a) many
(b) few
(c) more
(d) a lot
Answer:
(b) few

Question 4.
Please advise Our children how to
(a) reasonably
(b) foolishly use internet wisely.
(c) gently
(d) mildly
Answer:
(b) foolishly

Question 5.
Never chat with anybody.
(a) not at all
(b) not ever
(c) always
(d) without
Answer:
(c) always

Question 6.
Internet or mobile helps us to connect with people around the world.
(a) bond
(b) disconnect
(c) attach
(d) join
Answer:
(b) disconnect

Question 7.
Enjoy various other activities,
(a) different
(b) numerous
(c) same
(d) assorted
Answer:
(c) same

Question 8.
What happend? you seem dull.
(a) bright
(b) boring
(c) colourless
(d) heavy
Answer:
(a) bright

Question 9.
I am really scared.
(a) frightened
(b) nervous
(c) confident
(d) feared
Answer:
(c) confident

Question 10.
Don’t respond to his message
(a) answer
(b) ignore
(c) reply
(d) address
Answer:
(b) ignore

III. Give very short answers :

Question 1.
What did Gladin want to know?
Answer:
Gladin wanted to know the working of a screw gange.

Question 2.
What was the name of Gladin’s sister?
Answer:
Her name was Rani.

Question 3.
Why was Gladin gathering information in the internet?
Answer:
He was gathering information for his science project.

Question 4.
Does the stranger know Rani’s name?
Answer:
Yes, The stranger knows Rani’s name.

Question 5.
Who advises the children?
Answer:
The father advises the children.

Question 6.
What did he advise?
Answer:
He advises them never to chat with strangers.

Question 7.
What does the mother request her husband?
Answer:
She requested him to advise their children how to use internet wisely.

Question 8.
What are the power houses of entertainment?
Answer:
Internet and the mobile are the power houses of entertainment.

Question 9.
Is too much of anything is good?
Answer:
No, too much of anything is not good.

Question 10.
Can we ignore the beneficial of internet and mobile phones?
Answer:
No, we can’t ignore the beneficial of internet and mobile phones.

IV. Give short answers :

Question 1.
What is an Internet?
Answer:
An Internet is a great tool where we can gather information to gain knowledge.

Question 2.
What does the stranger do?
Answer:
The stranger chats with Rani everyday. He uses bad words and tells Rani not to disclose about him to anyone. Otherwise, he will cause harm to her family members.

Question 3.
How does the internet or mobile entertain us?
Answer:
The internet or mobile allow us to watch movies, listen to music, play games and enjoy various other activities.

Question 4.
Why should we limit the usage of internet or mobile phone?
Answer:
We should limit the usage of internet or mobile phone to take charge of our lives.

Question 5.
What personal details should be very private?
Answer:
Our photos, phone number, aadhar number and our interests should be very private.

V. Answer in detail:

Rani got scared of a stranger, who used to chat with her everyday. Rani said that he knew her name, address, age and everything. He also used bad words, while chatting with her. So her father advised her not to respond to stranger’s message, even if he continuously disturbed her. After some days, he might not chat. Still if he tried to disturb her, her father would take care of him. Her father would talk to his parents. So her father told Rani not to worry about the stranger anymore.

Cyber Safety Grammar – Additional

Simple, Compound, And Complex

I. State which of the following sentences are simple, compound, complex :

1. The baby cried for food.
2. They spoke to him in Spanish, but he responded in English.
3. Hearing their cries, we came out.
4. They ate too much yesterday.
5. As we won the match, we were appreciated by the committee.
6. He was poor but helped everyone.
7. After reaching home, he rang to his friend.
8. Open the door and close the windows.
9. He was the man who- met us yesterday.
10.You must hurry or you will be late to school.

Tense-Time

II. Fill in the blanks with correct form of the verbs in the brackets

1. He played football and then ______ home, (go)
2. He ______ five matches by then, (won)
3. They were ______ for you(look)
4. Shell’ll be ______ tonight.(come)
5. By this time she leaves, Jane ______ here for 3 years, (live)
6. He is ______ a book, (read)
7. He ______ , before 1 came back from the market, (sleep)
8. He ______ to London yesterday, (fly)
9. The light went out, while they ______ .(read)
10. He ______ when I called, (exercise)

Answer:

1. went
2. will have won
3. looking
4. coming
5. will have been living
6. reading
7. had slept
8. flew
9. were reading
10. had been exercising

Warm Up

What are the sacrifices made by your father for your family.

Cyber Safety Summary

This lesson is about the technology of the present world – its benefits and negative aspects. One day Gladin asked his mother about the working of a screw gauge. She advised him to browse about it in the internet.

He could gather information from it and gain knowledge. Rani, Gladin’s sister was frightened of something. When enquired by her father, she informed him that someone chatted with her and used bad words. The person had warned her not to discuss about the chat to anyone. Otherwise, he would cause harm to her family members.

Her father advised her not to respond to any of his messages. After some days, he would not chat. If the person bothered further, her father would report to the cyber police. Her father also advised the children not to chat with the strangers. They should keep all their personal details very private. They should not get addicted to the power house of entertainment. Mobile addiction causes several serious health problems. Yet, we cannot ignore the benefits of internet and mobile phone.

They are very useful to gain knowledge and gather information. But too much of anything is good for nothing. So we must limit their usage to take charge of our lives.

You can Download Samacheer Kalvi 8th Science Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Science Solutions Term 2 Chapter 2 Electricity

Samacheer Kalvi 8th Science Electricity Text Book Exercises

I. Chosse the best answer

8th Science Electricity Book Back Answers Question 1.
When an ebonite rod is rubbed with fur, the charge acquired by the fur is –
(a) negative
(b) positive
(c) partly positive and partly negative
(d) None of these
Answer:
(b) positive

Samacheer Kalvi 8th Science Book Solutions Term 2 Question 2.
The electrification of two different bodies on rubbing is because of the transfer of –
(a) neutrons
(b) protons
(c) electrons
(d) protons and neutrons
Answer:
(c) electrons

Samacheer Kalvi 8th Science Book Solutions Question 3.
Which of the following a simple circuit must have?
(a) Energy Source, Battery, Load
(b) Energy Source, Wire, Load
(c) Energy Source, Wire, Switch
(d) Battery, Wire, Switch
Answer:
(d) Battery, Wire, Switch

Samacheer Kalvi 8th Standard Science Question 4.
An electroscope has been charged by induction with the help of charged glassrod. The charge on the electroscope is –
(a) negative
(b) positive
(c) both positive and negative
(d) None of the above
Answer:
(b) positive

Samacheer Kalvi 8th Science Question 5.
Fuse is –
(a) a switch
(b) a wire with low resistanceFuse is
(c) a wire with high resistance
(d) a protective device for breaking an electric circuit
Answer:
(d) a protective device for breaking an electric circuit

II. Fill in the blanks

1. ……………. takes place by rubbing objects together.
2. The body which has not lost electrons becomes …………….
3. ……………. is a device that protects building from lightning strike.
4. ……………. has a thin metallic filament that melts and breaks the connection when the circuit is overheated.
5. Three bulbs are connected end to end from the battery. This connection is called …………….

Answer:

1. Transfer of electron
2. positive
3. Lightning arrestor
4. Electric fuse
5. series circuit

III. State True or False. If false, correct the statement

Question 1.
The charge acquired by an ebonite rod rubbed with a piece of flannel is negative.
Answer:
True

Question 2.
A charged body induces an opposite charge on an uncharged body when they are brought near.
Answer:
True

Question 3.
Electroscope is a device used to charge a body by induction.
Answer:
True

Question 4.
Water can conduct electricity.
Answer:
True

Question 5.
In parallel circuit, current remains the same in all components.
Answer:
False
Correct statement:
In parallel circuit, voltage remains the same in all components.

IV. Match the following

Question 1.

1. Two similar charges – acquires a positive charge
2. Two dissimilar charges – prevents a circuit from overheating
3. When glass rod is rubbed with silk – repel each other
4. When ebonite rod is rubbed with fur – attract each other
5. Fuse – acquires a negative charge

Answer:

1. Two similar charges – repel each other
2. Two dissimilar charges – attract each other
3. When glass rod is rubbed with silk – acquires a positive charge
4. When ebonite rod is rubbed with fur – acquires a negative charge
5. Fuse – prevents a circuit from overheating

V. Give reason for tile following.

Question 1.
When a glass rod is rubbed with silk cloth, both get charged.
Answer:
Reason:
When a glass rod is rubbed with a silk cloth the free electrons in the glass rod are transferred to silk cloth. It is because the free electrons in the glass rod are less tightly bound as compared to that in silk cloth. Since the glass rod looses electrons, it has a deficiency of electrons and hence acquires positive charge. But, the silk cloth has excess of electrons. So, it becomes negatively charged.

Question 2.
When a comb is rubbed with dry hair, it attracts small bits of paper.
Answer:
Reason:
Comb rubbed with hair gains electrons from the hair and becomes negatively charged. These electrons are accumulated on the surface of the comb. When a piece of paper is teared into bits, positive and negative charges are present at the edges of the bits. Negative charges in the comb attract positive charges in the bits. So, the paper bits are moving towards the comb.

Question 3.
When you touch the metal disc of an electroscope with a charged glass rod the metal leaves get diverged.
Answer:
Reason:
The leaves of an electroscope diverge because when a glass rod is touched on the metal disc, the charge travels through the metal rod to the leaves. Since, like charge repel, the charge travels till the leaves and then open up as both the leaves have like charges.

Question 4.
In an electroscope the connecting rod and the leaves are all metals.
Answer:
Reason:
These are made of metals so that the electrons become free to move.

Question 5.
One should not use an umbrella while crossing an open field during thunderstorm.
Answer:
Reason:

1. Carrying an umbrella is not advisable during thunderstorm.
2. As the rod of umbrella and its supporting wires are made up of metals.
3. Thus during thunderstorm, the conducting object should be avoided.

VI. Choose the correct answer from the following directions.

Question 1.
(a) If both assertion and reason are true and reason is the correct explanation of the assertion.
(b) If both assertion and reason are true and reason is not the correct explanation of assertion.
(c) If the assertion is true, but reason is false.
(d) If the assertion is false but reason is true.

Question 1.
Assertion : People struck by lightning receive a severe electrical shock.
Reason : Lightning carries very high voltage.
Answer:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.

Question 2.
Assertion : It is safer to stand under a tall tree during lightning.
Reason : It will make you the target for lightning.
Answer:
(d) The assertion is false but reason is true

VII. Answer briefly

Question 1.
How charges are produced by friction?
Answer:
Rubbing certain materials with one another can cause the built-up of electrical charges on the surfaces. So charges are produced by friction.
Example:
Combing hair charges are transferred from the hair to comb due to friction.

Question 2.
What is Earthing?
Answer:
Earthing is the process of connecting the exposed metal parts of an electrical circuit to the ground.

Question 3.
What is electric circuit?
Answer:
The path through which electrons flow from one terminal to another terminal of the source, is called electric circuit.

Question 4.
What is electroplating?
Answer:
The process of depositing a layer of one metal over the surface of another metal by passing electric current is called electroplating.

Question 5.
Give some uses of electroplating.
Answer:
Electro plating is applied in many fields:

1. We use iron in bridges and automobiles to provide strength.
2. A coating of zinc is deposited on iron to protect it from corrosion and formation of rust.
3. Chromium has a shiny appearance. It does not corrode.
4. It resists scratches.

VIII. Answer is detail

Question 1.
Explain three ways of charge transfer.
Answer:
Transfer of charges takes place in the following three ways:

1. Transfer by Friction
2. Transfer by Conduction
3. Transfer by Induction

1. Transfer by Friction:
This method of charging an uncharged body by rubbing it ; against another body is called charging by friction.
Example:
While combing hair charges are transferred from the hair to comb due to friction.

2. Transfer by conduction:
Charges can be transferred to on object by bringing it in contact with a charged body. This method of transferring charges from one body to other body is calledtransfer by conduction.
Example:
When the ebonite rod is rubbed with woollen cloth, electrons from the woollen cloth are transferred to the ebonite rod. Now ebonite rod will be negatively charged.

(i) When it is brought near the paper cylinder, negative charges in the rod are attracted by the positive charges in the cylinder.

(ii) When the cylinder is touched by the rod, some negative charges are transferred to the paper. Hence, the negative charges in the rod are repelled by the negative charges in the cylinder.

3. Transfer by Induction:
The process of charging an uncharged body by bringing a charged body near to it but without touching it is called induction.
Example:
we can charge an uncharged object when we touch it by a charged object. But, it is also possible to obtain charges in a body without any contact with other charges.

Question 2.
What is electroscope? Explain how it works?
Answer:
1. An electroscope is a scientific instrument used to detect the presence of electric charge on a body.

2. An electroscope is made out of conducting materials, generally metal.

3. It works on the principle that like charges repel each other.

4. In a simple electroscope two metal sheets are hung in contact with each other.

5. They are connected to a metal rod that extends upwards, and ends in a knob at the end.

6. If you bring a charged object near the knob, electrons will either move out of it or into it.

7. This will result in charges on the metal leaves inside the electroscope.

8. If a negatively charged object is brought near the top knob of the electroscope, it causes free electrons in the electroscope to move down into the leaves, leaving the top positive..

9. Since both the leaves have negative charge, they repel each other and move apart.

10. If a positive object is brought near the top knob of the electroscope, the free electrons in the electroscope start to move up towards the knob.

11. This means that the bottom has a net positive charge. The leaves will spread apart again. Explain series and parallel circuit.

Question 3.
Explain series and parallel circuit.
Answer:
Series Circuit:

1. A series circuit is one that has more than one resistor (bulb) but only one path through which the electrons can travel.
2. From one end of the battery the electrons move along one pathwith no branches through the resistors (bulbs) to the other end of the cell.
3. All the components in a series circuit are connected end to end.
4. So, current through the circuit remains same throughout the circuit.
5. But, the voltage gets divided across the bulbs in the circuit.
6. In the following series circuit two bulbs are used as resistors.
7. Let I be the current through the circuit and V₁ V₂, V₃ be the voltage across each bulb.
8. The supply voltage V is the total of the individual voltage drops across the resistances. V = V₁ + V₂ + V₃

Parallel Circuit:

1. In a parallel circuit, there is more than one resistor (bulb) and they are arranged on many paths.
2. This means charges (electrons) can travel from one end of the cell through many branches to the other end of the cell.
3. Here, voltage across the resistors (bulbs) remains the same but the current flowing through the circuit gets divided across each resistor.
4. Let us consider three bulbs connected in series.
5. Let V be the voltage across the bulbs and I₁, I₂, I₃ be the current across each bulb.
6. The current I from the battery is the total of the individual current flowing through the resistances. I = I₁ + I₂ + I₃

Question 4.
How lightning takes place?
Answer:
1. Lightning is produced by discharge of electricity from cloud to cloud or from cloud to ground.

2. During thunderstorm air is moving upward rapidly.

3. This air which moves rapidly, carries small ice crystals upward.

4. At the same time, small water drops move downward.

5. When they collide, ice crystals become positively charged and move upward and the water drops become negatively charged and move downward.

6. So the upper part of the cloud is positively charged and the lower part of the cloud is negatively charged.

7. When they come into contact, electrons in the water drops are attracted by the positive charges in the ice crystals. Thus, electricity is generated and lightning is seen.

8. Sometimes the lower part of the cloud which is negatively charged comes into contact with the positive charges accumulated near the mountains, trees and even people on the earth. This discharge produces lot of heat and sparks that results in what we see as lightning.

Question 5.
What is electroplating? Explain how it is done.
Answer:
Electroplating:

1. Electroplating is one of the most common applications of chemical effects of electric current.
2. The process of depositing a layer of one metal over the surface of another metal by passing electric current is called electroplating.
3. Take a glass jar and fill it with copper sulphate solution.
4. Take a copper metal plate and connect it to the positive terminal of battery.
5. Connect an iron spoon to the negative terminal of the battery.
6. Now, dip them in the copper sulphate solution.
7. When electric current is passed through the copper sulphate solution, you will find that a thin layer of copper metal is deposited on the iron spoon and an equivalent amount of copper is lost by the copper plate.

Samacheer Kalvi 8th Science Electricity Intex Activities

Activity – 1

Question 1.
Take a comb and place it near some pieces of paper. Are they attracted by the comb? No. Now comb your dry hair and place it near them. What do you see? You can see that the paper pieces are attracted by the comb now. How is it possible?
Answer:
Reason:
Comb rubbed with hair gains electrons from the hair and becomes negatively charged. These electrons are accumulated on the surface of the comb. When a piece of paper is teared into bits, positive and negative charges are present at the edges of the bits. Negative charges in the comb attract positive charges in the bits. So, the paper bits are moving towards the comb.

Activity – 2

Question 1.
Take a sheet of paper. Turn it into a hollow cylinder. Tie one end of the cylinder with a silk thread and hang it from a stand. Now take an ebonite rod and charge it by rubbing it with a woollen cloth. Bring this charged ebonite rod near the paper cylinder. The cylinder will be attracted by the rod. If you touch the paper cylinder by the charged rod, you will see the paper cylinder repelling the rod. Can you give the reason?
Answer:
When the cylinder is touched by the rod, some negative charges are transferred to the paper. Hence, the negative charges in the rod are repelled by the negative charges in the cylinder.

Activity – 4

Question 1.
Rub your foot on a carpet floor and touch a door knob. What do you feel? Do you feel the shock in your hand? Why does this happen?
Answer:

Getting a shock from a doorknob after rubbing your foot on a carpet floor, results from discharge. Discharge occurs when electrons on the hand are quickly pulled to the positively charged doorknob. This movement of electrons, which is felt as a shock, causes the body to lose negative charge.

Activity – 5

Question 1.
Take two pieces of wire, an LED light and a battery, and make a simple electric circuit. Take some water in a glass and put the wires in the water as shown in the figure. Does the LED bulb glow? What do you understand from this?

Answer:
Yes, the LED bulb glows. From this Activity we understood that liquids also conduct electricity.

Activity – 7

Question 1.
Take a battery, a bulb, a switch and few connecting wires. Make an electric circuit as shown in the figure. Keep the switch in the ‘OFF’ position. Does the bulb glow?
Answer:
No, the bulb does not glow.

Question 2.
Now move the electric switch to the ‘ON’ position and let the bulb glow for a minute or so. Touch the bulb now. Do you feel the heat?
Answer:
Yes, the bulb is hot because electrical energy is transformed to heat energy. This is known as heating effect of electric current.

Samacheer Kalvi 8th Science Electricity Additional Questions

I. Choose the correct answer

Question 1.
Electroplating is based on ……………… effect of electricity.
(a) magnetic
(b) chemical
(c) heating
(d) physical
Answer:
(b) chemical

Question 2.
A positively charged object will attract ……………… charged object.
(a) positively
(b) negatively
(c) both a and b
(d) none
Answer:
(b) negatively

Question 3.
The method of charging an object by touching is called ………………
(a) induction
(b) diffusion
(c) current
(d) conduction
Answer:
(d) conduction

Question 4.
Lighting occurs due to ……………….
(a) rain
(b) humidity
(c) wind
(d) electric discharge
Answer:
(d) electric discharge

Question 5.
Electric charge can be transferred from a charged object to another through ……………….
(a) vacuum
(b) conductor
(c) air
(d) insulator
Answer:
(b) conductor

Question 6.
Electric charge is measured in ……………….
(a) volt
(b) coulomb
(c) ampere
(d) watt
Answer:
(b) coulomb

Question 7.
The value of charge of an electron is equal to ……………….
(a) 6.04 x 10^-19 C
(b) 1.602 x 10^-18 C
(c) 1.602 x 10^-19 C
(d) 6.10 x 10^-18 C
Answer:
(c) 1.602 x 10^-19 C

Question 8.
Before using electroscope, it should be ………………..
(a) charged
(b) closed
(c) discharged
(d) cleaned
Answer:
(c) discharged

Question 9.
Lighting rods are made of ………………..
(a) copper
(b) plastic
(c) sand paper
(d) wood
Answer:
(a) Copper

Question 10.
Electricity produced on rubbing is ……………….
(a) static electricity
(b) current electricity
(c) electromagnet
(d) none
Answer:
(a) static electricity

Question 11.
The materials which allows electric current to pass through it, is called ……………….
(a) conductor
(b) insulator
(c) both a and b
(d) none of these
Answer:
(a) conductor

Question 12.
The material which does not allow electric current is called ………………..
(a) solution
(b) metal
(c) insulator
(d) electrolyte
Answer:
(c) insulator

Question 13.
All metals are ………………..
(a) conductors
(b) insulators
(c) electrolytes
(d) none
Answer:
(a) conductors

Question 14.
An electrolyte ……………….
(a) has positive charge
(b) has negative charge
(c) should be able to conduct charge without dissociating.
(d) should be able to form positive and negative ions.
Answer:
(d) should be able to form positive and negative ions

Question 15.
Most common industrial application of chemical effects of electric current is ………………..
(a) Anodizing
(b) electroplating
(c) electrolysis
(d) none
Answer:
(b) electroplating

Question 16.
The terminal which is connected to a positive terminal of a battery is called ……………….
(a) anode
(b) cathode
(c) neutral
(d) none
Answer:
(a) anode

Question 17.
Flow of per unit time is called current ………………..
(a) charge
(b) proton
(c) neutron
(d) all of these
Answer:
(a) charge

Question 18.
Liquids that conduct electricity are the solutions of ………………..
(a) acids
(b) bases
(c) salts
(d) all of these
Answer:
(d) all of these

Question 19.
A tiny particle which rotates around the nucleus of an atom is ………………..
(a) proton
(b) electron
(c) neutron
(d) both a and b
Answer:
(b) electron

Question 20.
……………….. wire is used in the filament of the bulbs.
(a) Nichrome
(b) Copper
(c) Tungsten
(d) None
Answer:
(c) Tungsten

II. Fill in the blanks

1. Comb rubbed with hair ……………. electrons from the hair and becomes negatively charged.
2. Electric charge is measured in ……………..
3. Since, protons and electrons are equal in number, an atom is electrically ………………
4. When an ebonite rod is rubbed with fur, the fur transfers …………….. to the ebonite rod.
5. Before the discovery of electrons, it was considered that electric current is due to the flow of …………….. charges.
6. The gold – leaf electroscope was developed by ………………
7. …………….. is an example of discharge that takes place in clouds.
8. During thunderstorm air is moving …………….. rapidly.
9. Huge quantities of electricity are discharged in light flashes and temperatures of over ……………..°C or more can be reached.
10. …………….. extreme heat will vaporize the water inside a tree, creating steam that may bum out the tree.
11. …………….. is a device used to protect buildings from the effects of lightning .
12. …………….. is a species offish which can give electric shocks.
13. In series circuit, the current remains …………….. throughout the circuit.
14. …………….. is used in extraction and purification of metals.
15. Copper wire offers very little …………….. and does not get heated up quickly.
16. A fuse is a strip of alloy wire which is made of lead and tin with a very low ………………
17. The flow of ……………… per unit time is called current.

Answer:

1. gains
2. coulomb
3. neutral
4. electrons
5. positive
6. Abraham Bennet
7. Lightning
8. upward
9. 30,000
10. Lightning’s
11. Lightning arrestor
12. Electric eel
13. same
14. Electrolysis
15. resistance
16. melting point
17. charge

III. True or False – if false give the correct statement

Question 1.
Materials which do not allow electric charges to pass through them easily are called insulator.
Answer:
True

Question 2.
Silk cloth has excess of electrons, so it becomes positively charged.
Answer:
False
Correct statement:
Silk cloth has excess of electrons, so it becomes negatively charged.

Question 3.
Electric charge is measured in coulomb.
Answer:
True.

Question 4.
Protons carry negative charge and the electrons carry positive charge.
Answer:
False.
Correct statement:
Protons carry positive charge and the electrons carry negative charge.

Question 5.
The gold – leaf electroscope was developed by Abraham Bennet.
Answer:
True

IV. Match the following

Question 1.

Answer:

1. c
2. d
3. b
4. a

Question 2.

Answer:

1. b
2. c
3. d
4. a

Question 3.

Answer:

1. d
2. c
3. a
4. b

V. Read the directions given below and answer the questions.

Question 1.
(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.
(b) If both assertion and reason are true, but the reason is not the correct explanation of the assertion.
(c) If the assertion is true, but the reason is false.
(d) If the assertion is false, but the reason is true.

Question 1.
Assertion : Charges flow from higher potential to the lower potential.
Reason : Current flows mainly due to flow of electrons.
Answer:
(b) Both assertion and reason are true, but the reason is not the correct explanation of the assertion

Question 2.
Assertion : Parts of car and bicycle are made iron with chromium coating.
Reason : Chromium does not corrode and resist scratches.
Answer:
(a) Both assertion and reason are true and the reason is the correct explanation of the assertion

Question 3.
Assertion : Insulators do not allow flow of current through them.
Reason : Insulators have no free charge carrier
Answer:
(a) Both assertion and reason are true and the reason is the correct explanation of the assertion

Question 4.
Assertion : A current carrying wire should be charged.
Reason : The current in a wire is due to flow of free electrons in a definite direction.
Answer:
(d) The assertion is false, but the reason is true

Question 5.
Assertion : When both the strips of electroscope is charged with similar charge, they repel each other and become wide open.
Reason : Like charges always repel each other.
Answer:
(a) Both assertion and reason are true and the reason is the correct explanation of the assertion

VI. Answer briefly

Question 1.
Name the process which show the chemical effect of electric current?
Answer:
Electroplating.

Question 2.
What are electrodes?
Answer:
The metal rods dipped in liquids to which cells are attached are called electrodes.

Question 3.
Who discovered static electricity or lightning in clouds?
Answer:
Benjamin Franklin in 1752.

Question 4.
What are charged objects?
Answer:
The objects which acquire a small charge on rubbing are called charged objects.

Question 5.
What do you mean by earthing?
Answer:
The process of transferring of charge from a charged object to the earth is called earthing.

Question 6.
A layer of zinc coated over iron. Why?
Answer:
Layer of zinc coated over iron because zinc prevents it from rust and corrosion.

Question 7.
Name the effect of current responsible for the glow of the bulb in an electrical circuit.
Answer:
Heating effect of electric current.

Question 8.
Name a few appliances which work on the basis of heating effect of current.
Answer:
Bulb, iron, heater, electric kettles, electric cookers, electric fuse.

Question 9.
What are the essential components of an electric circuit?
Answer:
Electric cell, bulb, switch, battery and connecting wires.

Question 10.
How can you save yourselves from lightning?
Answer:

1. We should remain in the covered area.
2. we should not use wired telephones during lightning.

Question 11.
State some advantages electroplating.
Answer:

1. It protects the metal from corrosion and rusting.
2. It is used to coat desired metal on other objects.
3. It can make more reactive metal like iron.
4. Coating of chromium on the metal gives luster to the objects.

Question 12.
Write the differences between conductors and insulators.
Answer:
Conductors:
Materials which allow the electric current to pass through them are called conductors.
Example:
All metals, Salt water

Insulators:
Materials do not allow the current to pass through them are called insulators.
Example:
Dry wood, plastics, rubber, glass

Question 13.
What are anodes and cathodes?
Answer:

1. In the process of electrolysis, the electrode which is connected to the positive terminal of the battery is called anode.
2. The electrode which is connected to the negative terminal of the battery is called cathode.

Question 14.
What will be the charges on silk and glass rod when they are rubbed against each other?
Answer:

1. When a glass rod is rubbed with silk piece, the free electrons in the glass rod are transferred to silk piece.
2. It is because the free electrons in the glass rod are tightly bound as compared to that in silk piece.
3. Since the glass rod looses electrons, it has a deficiency of electrons and hence acquires positive charge.
4. But, silk piece has excess of electrons.
5. So, it becomes negatively charged.

Question 15.
When a negatively charged glass rod is brought near another glass rod, the rod will move apart. Give reason.
Answer:
It is because both the glass rods are negatively charged. So they repel each other.

Question 16.
When an ebonite rod is rubbed with fur, the fur transfers electrons to the ebonite rod. Why?
Answer:

1. It is because the electrons in the outermost orbit of the atoms in fur are loosely bound as compared to the ebonite rod.
2. Ebonite rod has excess electrons which becomes negatively charged and the fur which has deficiency of electrons is positively charged.

Question 17.
List the ways in which you can charge an object.
Answer:

1. Charging by friction
2. Charging by induction
3. Charging by conduction.

Question 18.
How thunder takes place?
Answer:

1. Huge, quantities of electricity are discharged in lightning flashes and temperatures of over 30,000°C or more.
2. This extreme heat causes the air to expand explosively fast and then they contract.
3. This expansion and contraction create a shock wave that turns into a booming sound wave known as thunder.

Question 19.
Sometimes lighting may be seen before the thunder is heard. Why?
Answer:
It is because the distance between the clouds and the surface is very long and the speed of light is much faster than the speed of sound.

Question 20.
What do you mean by electrical Earthing?
Answer:
Electrical Earthing is defined as the process of transferring the discharge of electrical energy directly to the Earth With the help of low-resistance wire.

VII. Answer in detail

Question 1.
Explain the structure and working of gold-leaf electroscope with a diagram.
Answer:

Structure of I metroscope :

1. It is made up of a glass jar.
2. A vertical brass rod is inserted into the jar through a cork.
3. The top of the brass rod has a horizontal brass rod or a brass disc.
4. Two gold leaves are suspended from the brass rod inside the jar.

Working of Electroscope:

1. When the brass disc of the electroscope is touched by a charged object, electric charge
2. gets transferred to the gold leaf through the rod.
3. This results in the gold leaves moving away from each other.
4. This happens because both the leaves have similar charges.

Question 2.
Write a note on –

1. Charging
2. Electrical discharge.

Answer:
1. Charging:
Transfer of charge from one object to another is called charging. In case of the gold leaves charge is transferred through the brass rods.

2. Electrical Discharge:
The gold leaves resume their normal position after some time. This happens because they lose their charge. This process is called electrical discharge. The gold leaves would also be discharged when someone touches the brass rod with bare hands. In that case, the charge is transferred to the earth through the human body.

Question 3.
Explain the function of lightning arrestor with a diagram.
Answer:

1. Lightning arrestor is a device used to protect buildings from the effects of lightning.
2. Lightning conductor consists of a metallic lightning rod that remains in air at the top of the building.
3. Major portion of the metal rod and copper cable are installed in the walls during its construction.
4. The other end of the rod is placed deep into the soil.
5. When lightning falls, it is attracted by the metallic rods at the top of the building.
6. The rod provides easy route for the transfer of electric charge to the ground.
7. In the absence of lightning arrestors, lightning will fall on the building and the building will be damaged.

Question 4.
Write a note on.

1. Fuse
2. Electric irons.

Answer:
1. Fuse:

1. Fuse is a strip of alloy wire which is made up of lead and tin with a very low melting point.
2. This can be connected to the circuit.
3. The fuse is usually designed to take specific amount of current.
4. When current passing through the wire exceeds the maximum limit, it gets heated up.
5. Due to low melting point, it melts quickly disconnecting the circuit. This prevents damage to the appliances.

2. Electric irons :

1. When current flows through the heating element, the heat energy developed is conducted to the heavy metal base, raising its temperature.
2. This energy is then used to press clothes.

Question 5.
Distinguish between series and parallel circuit.
Answer:
Series circuit:

1. Same amount of current flows through all the components.
2. Voltage is different across different components.
3. Components are arranged in a line.
4. If one component breaks down, the whole circuit will bum out.

Parallel circuit:

1. The current flowing through each component combines to form the current flow.
2. Sum of the voltage through each component will be the voltage drawn from the source.
3. Components are arranged parallel to each other.
4. Other components will function even if one component breaks down.

VIII. Picture based Questions

Question 1.
Will the bulb glow if the end B is dipped in pure water?

Answer:
No, the bulb will not glow as pure water is an insulator.

Question 2.
Identify the charge on the body with a question mark.

Answer:

Question 3.
The bulb does not glow in the set up show in figure. List the possible reasons.

Answer:
The possible reasons are:

1. Bulb may be fused.
2. Cells may be used up.
3. The liquid may be poor conductor of electricity.
4. The connection of the circuits may be loose.

IX. Higher Order thinking skills (HOTS):

Question 1.
During the construction of a building, the lightning conductor was left hanging in the air by mistake will it be effective? Explain.
Answer:
Lighting conductor will not work. It left hanging in the air because in order to work, it must be installed properly and grounded using copper plate.

Question 2.
During lightning and thunder we should avoid standing in ground and open spaces Why?
Answer:
During lightning and thunder, we should avoid standing in ground and open spaces. You should make yourself as small as possible by squating. It is however safe to stay inside a car because the car acts as a shield and protects us from the electric field generated by the storm.

Question 3.
You might have observed on a dry day that when you touch the screen of a television you get a slight shock. Why does it happen?
Answer:
It happens because the television screen is charged and have static charges and when we touch with our hands which are uncharged, the charges attract our hands and transfer through our hands and we get a small shock.

X. Solve the following crossword with the help of the given clues.

Clue:
Across :
1. Ions having a positive charge formed by the loss of electrons.
2. Chemical compound which conducts electricity when in aqueous state.
5. Atoms that have an electric charge.
7. A piece of metal through which an electric current enters or leaves in a liquid or gas.

Down :
3. A process in which a thin film of metal is deposited on another metal with the help of electricity.
4. A process in which a chemical change especially decomposition of a chemical compound is brought about by passing an electric current through a solution.
6. Ions having a negative charge formed by the gain of electrons.
8. The negative electrode is an electrolytic cell, toward which positively charged particles are attracted.
Answer:

You can Download Samacheer Kalvi 8th Science Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Science Solutions Term 1 Chapter 8 Organisation of Life

Samacheer Kalvi 8th Science Solutions Organisation of Life Text Book Exercises

I. Choose the correct answers

Organisation Of Life 8th Standard Question 1.
……………… is tough and thick white sheath that protect the inner parts of the eye.
(a) Sclera
(b) Conjunctiva
(c) Cornea
(d) Iris
Answer:
(a) Sclera

8th Science Organisation Of Life Question 2.
Maintenance of constant internal environment of the body is known as ………………
(a) Homeostasis
(b) Homeophytes
(c) Homeokinesis
(d) Homeophilics
Answer:
(a) Homeostasis

Organisation Of Life Question 3.
In the absence of oxygen, glucose is broken down into ………………
(a) Lactic acid
(b) Citric acid
(c) Acetic acid
(d) Nitric acid
Answer:
(a) Lactic acid

Samacheer Kalvi 8th Biology Book Solutions Question 4.
……………… cells are specialised cells that can be transformed into any kind of cells.
(a) Nerve
(b) Stem
(c) Heart
(d) Bone
Answer:
(b) Stem

Samacheer Kalvi Guru 8th Science Question 5.
The process of air passing in and out the lungs is called ………………
(a) Inhalation
(b) Exhalation
(c) Breathing
(d) None of these
Answer:
(c) Breathing

Samacheer Kalvi.Guru 8th Science Question 6.
Osmosis is the movement of water molecules from a ………………
(a) Higher concentration to a region of lower concentration.
(b) Lower concentration to a region of higher concentration.
(c) Both of these
(d) None of these
Answer:
(a) Higher concentration to a region of lower concentration

Samacheer Kalvi Guru 8 Science Question 7.
The erythrocyte is placed in ……………… solution which has lesser concentration of solutes and greater concentration of water than in the cytoplasm.
(a) Hypotonic
(b) Hypertonic
(c) Neutral
(d) Acidic
Answer:
(a) Hypotonic

II. Fill in the blanks

1. ……………… is the structural and functional unit of living organisms.
2. The largest cell is egg of an ………………
3. ……………… is a good example for anaerobic respiration.
4. ……………… nerve is located at the end of the eyes behind the retina.
5. The size of the cells are measured in units of ………………

Answer:

1. Cell
2. Ostrich
3. Fermentation
4. Optic
5. Microns

III. Write true or False. If false, give the correct answer

Samacheer Kalvi Guru 8th Standard Science Question 1.
In hypotonic condition, concentration of the external and the internal solution of the organism are same.
Answer:
False.
Correct statement:
The concentration of external solution is less compared to concentration of internal solution of the organism.

Organization Of Life Question 2.
Diffusion is the movement of particles from an area of lower concentration to higher concentration.
Answer:
False.
Correct statement:
Diffusion is the movement of particles from an area of higher concentration to lower concentration.

Samacheer Kalvi Guru 8th Question 3.
Human beings are warm blooded in nature.
Answer:
True.

Organization Of Life Definition Question 4.
The larynx has fold of tissue which vibrate with the passage of air to produce.
Answer:
True.

Organization Of Life Worksheet Question 5.
Aqueous humour plays an important role in maintaining the shape of the eye.
Answer:
True.

V. Arrange the following words in correct sequence

Question 1.
Tissues, organ system, organism, cell, organ
Answer:
Cell, tissues, organ, organ system, organism.

VI. Answer in brief

Question 1.
What is cell differentiation?
Answer:
Our body develops from a single cell called zygote. The zygote undergoes mitotic division to form many cells of different shape, size and content. These cells attain change in structure and function which is called differentiation. This form the foetus.

Question 2.
State different types of tissues.
Answer:
Depending on the basis of their structure and function, tissues can be classified into four types.

1. Epithelial (covering) tissue for protection.
2. Muscular (contractile) tissue for movements and locomotion.
3. Connective (supporting) tissue for binding different structures of body.
4. Nervous tissue for conduction of nerve impulses.

Question 3.
Mention the function of ‘Alveoli’?
Answer:

1. Alveoli are tiny air sacs in the lungs.
2. They are the workhouses of the respiratory system.
3. The exchange of oxygen and carbon dioxide take place in alveoli of the lungs.

Question 4.
Name the processes by which air enters and comes out of our lungs?
Answer:

1. The process of taxing air into the lungs is called inspiration or inhalation.
2. The process of expelling air from the lungs is called expiration or exhalation.

Question 5.
Differentiate between Osmoconformers and Osmoregulators?
Answer:
There are two major types of Osmoregulation:
Osmoconformers:
These organisms try to maintain the osmolality of their body matching with their surroundings. Most of the invertebrates, marine organisms are osmoconformers.

Osmoregulators:
These organisms maintain their internal osmolality, which can be extremely different from that of the surrounding environment, through physiological processes.

Question 6.
Define Metabolism?
Answer:

1. Metabolism is the sum of chemical reactions by which living organisms sustain their life.
2. Metabolism consists of anabolism (the buildup of substances) and catabolism (the breakdown of substances).

VII. Answer in few words

Question 1.
Define Prokaryotic cell?
Answer:
Organisms in which no true nucleus is seen are called prokaryotic. Ex : Bacteria.

Question 2.
Define Eukaryotic cell?
Answer:
Organisms in which true nucleus is seen (presence of nuclear membrane) are called eukaryotic. Ex : Higher plants.

Question 3.
Tabulate the difference between aerobic and an anaerobic respiration.
Answer:

Question 4.
State different types of epithelial cells?
Answer:
The epithelial tissue is a tissue which acts as a covering and protects the underlying tissues. It is classified into the following types.

1. Squamous epithelium.
2. Cuboidal epithelium.
3. Columnar epithelium.
4. Ciliated epithelium.
5. Glandular epithelium.

Question 5.
Why the human eye is compared with camera?
Answer:
The human eye can be compared to a camera as both functions by gathering, focusing, and transmitting the light through the lens for creating an image of an object.

1. The iris of the eye controls the size of the pupil depending on the amount of light entering it.
2. The pupil is like the eyehole of a camera which allows light to come in.
3. Lens : It is a transparent, biconvex, and an adjustable part of an eye, made up of protein. The lens with the help of the cornea refracts light focused on the retina, therefore creating images on it.
4. The retina consists of photoreceptors and converts light rays into impulses to be sent to the brain. It is light sensitive.
   The retina is compared to the film in a camera.

Question 6.
Which organ and organ system help to maintain homeostasis?
Answer:

1. Homeostasis is a property of a human biological system where the self – regulating process tends to maintain the balance for the survival.
2. Behavioural and physiological responses are two important regulating mechanisms that maintain the stability of homeostasis.
3. All the processes of integration and co – ordination of function are mediated by nervous and hormonal system. The liver, kidneys, and brain (hypothalamus), autonomic nervous system and the endocrine system help to maintain homeostasis.

VIII. Answer in detail

Question 1.
Draw the V.S of human eye and label its parts.
Answer:

Question 2.
Explain Osmosis with an example.
Answer:
Osmosis is the movement of solvent particles across a semipermeable membrane from a dilute solution into a concentrated solution. The solvent moves to dilute the concentrated solution and equalize the concentration on both sides of the membrane. The movement of liquids in and out cells is dependent on the concentration of the solution surrounding it. There are 3 types of situations in which this could vary:

1. Isotonic:
Here the concentration of external and internal solution of the organism are the same.

2. Hypotonic:
Here the external solution concentration is less compared to the concentration of the inner solution of an organism. In this case water will rush into the organism.

3. Hypertonic:
Here the external solution concentration is greater than the concentration of the inner solution of an organism. In this case the water will rush out of the organism.
Example:
Red blood cells.

1. When red blood cells are placed in hypertonic solution, water flows out of the cell faster than it comes in. This results in shrivelling of RBC.
2. On the other hand if RBC is hypotonic, more water will flow into the cell than out. This results in swelling of the cell and followed by bursting.
3. If the RBC is placed in an isotonic solutions, the flow of water in and out of the cell will happen at the same rate.

Question 3.
Differentiate between inhalation and exhalation.
Answer:
Inhalation:

• The muscles of the diaphragm contract.
• The diaphragm goes downward.
• The ribs move upwards and outwards.
• The volume of thoracic (chest) cavity increases.
• Air enters the lungs through the nose.

Exhalation:

• The muscles of the diaphragm relax.
• The diaphragm goes upward.
• The ribs move downwards.
• The volume of thoracic (chest) cavity decreases.
• Air goes out of the lungs through the nose.

Question 4.
Explain about the types of metabolism with an example.
Answer:

1. Metabolism is the sum of chemical reactions by which living organisms sustain their life.
2. Metabolism consists of anabolism (the buildup of substances) and catabolism (the breakdown of substances).

Anabolism:
Anabolism or constructive metabolism, is all about building and storing. It supports the growth of new cells, the maintenance of body tissues, and the storage of energy for use in the future. During anabolism, small molecules are changed into larger, more complex molecules of carbohydrate, protein and fat.

For example,
Glucose → Glycogen and other sugars
Amino acids → Enzymes, hormones and proteins

Catabolism:
Catabolism or destructive metabolism, is the process that produces the energy required for all activity in the cells. In this process, cells break down large molecules (mostly carbohydrates and fats) to release energy. This energy release provides fuel for anabolism, heats the body, and enables the muscles to contract and the body to move.
Carbohydrates → Glucose
Glucose → CO₂, Water and heat

Question 5.
Explain the mechanism of breathing.
Answer:

1. The process of taking air into the lungs is called inspiration or inhalation.
2. During inspiration, the sternum is pushed up and outward and the diaphragm is pulled down.
3. This increases the volume of the thoracic cavity and the pressure decreases.
4. The air outside the body flows into the lungs. Here exchange of gases takes place between the air and the blood.
5. The process of expelling air from the lungs is called expiration or exhalation. Upon exhalation, the lungs recoil to force the air out of the lungs.
6. The intercostal muscles relax, returning the chest wall to its original position. During exhalation, the diaphragm also relaxes, moving higher into the thoracic cavity.
7. This increases the pressure within the thoracic cavity relative to the environment.
8. Air rushes out of the lungs due to the pressure gradient. This movement of air out of the lungs is a passive event.

Question 6.
Read the given paragraph about human eye carefully and correct the mistakes. Our eye is cylindrical shaped. The wall of the eyeball is composed of five layers. The outermost layer is cornea. The innermost layer is called sclera. The eyeball consists of elastic nerves and biconcave lens. The pupil attaches lens to iris. Iris has rod and cone shaped cells. Aqueous humour is present between lens and retina. The vitreous humour is present between cornea and lens. The brain changes the light into nerve impulses and sends them to retina.
Answer:
Our eye is cylindrical shaped. The wall of the eyeball is composed of three layers. The outermost layer is sclera. The innermost layer is called retina. The eyeball consists of elastic nerves and biconvex lens. The pupil attaches lens to ciliarybody. Retina has rod and cone shaped cells. Vitreous humour is present between lens and retina. The aqueous humour is present between cornea and lens. The retina changes the light into nerve impulses and sends them to brain.

IX. HOT Questions

Question 1.
Why do we need instant energy? Does glucose give that energy? Explain.
Answer:

1. Energy is needed for performing day to day activities of the body which is got through intake of food. This provides energy for all organ systems.
2. Instant energy may be required in cases of extended physical activities like running or physical ailments like tiredness or giddiness.
3. Glucose is the simplest form of carbohydrate. Intake of glucose help it to solubilise in the blood immediately, and is carried to organs of the body thus helping to provide instant energy digestion of carbohydrates also converts it to glucose finally.

Question 2.
How are they preparing pickles? What are the causes involved in that?
Answer:

1. Pickles are prepared usually by addition of excess salt. The salty solution creates a high concentration (hypertonic) in the external medium of the vegetable / fruit which is used for making pickles.
2. Therefore water comes out of the vegatable and it undergoes plasmolysis and begins to shrink.
3. Thus when water content is lost the pickle is able to retain its shelf life for a longer period.

X. Value Based Questions

Question 1.
Dr. Usha is a pulmonologist (Doctor for respiratory diseases). One day, a school student named Arjun, met her with respiratory problems. After diagnosis, the doctor advised him to go playground daily and play football or basketball. She also advised to do pranayamam in the morning.
(a) Why did the doctor advised him to go to the playground?
(b) What is the use of pranayamam?
Answer:
(a) Playing is a good physical activity which helps to improve breathing and blood circulation in the body. It also helps to relieve anxiety.

(b)

1. Pranayamam teaches us the proper way of breathing, slowly and deeply.
2. It increases the capacity of the lungs and brings more oxygen into the body.
3. It is especially very useful when one has respiratory problems and the breathing is irregular and unsteady.
4. It improves blood circulation.

Question 2.
Explain why are you not able to breathe normally when you are in closed and crowded places?
Answer:
In a closed and crowded place, the number of people are more. All of them breathe out carbon dioxide. Therefore the amount of CO₂ in the air is much more than the amount of oxygen available for inhalation. Therefore we find it difficult to breathe in a closed and crowded place.

Question 3.
Shylesh is a school going kid studying standard VIII. He is crazy about playing video games in mobile phones. After couple of months, his eyes turned red and he felt severe pain in his eyes. His science teacher enquired about this and advised his parents to take him to consult an eye doctor.
(i) How does excessive usage of mobile phone affect our eyes?
(ii) What are the values shown by the teacher?
Answer:
Impact of excessive usage of mobile phones:

(i)

1. Cell phone radiation can damage eyes and cause early cataract.
2. It can also lead to cataract in lens apart from affecting retina, cornea etc.
3. It strains the eye muscles.
4. It also caused temporary problems like dry and itchy eyes, blurry vision, pain in eyes etc.

(ii) The teacher has shown values of:

1. Empathy
2. Responsibility
3. Personal care.

Samacheer Kalvi 8th Science Solutions Organisation of Life Additional Questions

I. Choose the correct answer

Question 1.
………………. is a type of connective tissue.
(a) Bone
(b) Cardiac muscle
(c) Neuron
(d) Ciliated epithelium
Answer:
(a) Bone

Question 2.
………………. is a transparent layer.
(a) Sclera
(b) Cornea
(c) Choroid
(d) Retina
Answer:
(b) Cornea

Question 3.
is not an example of diffusion.
(a) Tea bags in hot water
(b) Incense sticks
(c) Exchange of respiratory gases
(d) Pickling
Answer:
(d) Pickling

Question 4.
Each glucose molecule produces ATP.
(a) 38
(b) 40
(c) 36
(d) 34
Answer:
(c) 36

Question 5.
…………….. of the eye is comparable to film of a camera.
(a) Retina
(b) Sclera
(c) Lens
(d) Cornea
Answer:
(a) Retina

II. Fill in the Blanks

1. The smallest cell in human body is ………………
2. The coloured portion of the eye is the ………………
3. The transparent membrane that keeps the eye moist is ……………..
4. The lungs are covered by a membrane called …………….
5. The voice box is called ……………..

Answer:

1. Red blood cell
2. Iris
3. Conjunctiva
4. Pleura
5. Larynx

III. True or False – if false give the correct statement

Question 1.
Blood is a fluid connective tissue.
Answer:
True.

Question 2.
Stem cells can serve as inbuilt repair system for our body.
Answer:
True.

Question 3.
Ribosome is an organelle seen in prokaryotes and eukaryotes.
Answer:
True.

Question 4.
The wind pipe is called larynx.
Answer:
False.
Correct statement:
The wind pipe is called trachea.

Question 5.
No energy is produced in anaerobic respiration.
Answer:
False.
Correct statement:
Less energy is produced in anaerobic respiration.

IV. Match the following

Question 1.

Answer:

i. b
ii. a
iii. d
iv. c

Question 2.

Answer:

i. d
ii. c
iii. a
iv. b

V. Assertion and Reason

Direction:
In each of the following questions, a statement of Assertion is given and a corresponding statement of Reason is given just below it. Of the four statements, given below, mark one as the correct answer.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true and Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If both Assertion and Reason are false.

Question 1.
Assertion : During inhalation, the diaphragm goes downward.
Reason : The volume of thoracic cavity decreases.
Answer:
(c) Assertion is true but Reason is false

Question 2.
Assertion : Diffusion of molecules occurs through a semipermeable membrane.
Reason : Molecules of gases are only involved in diffusion.
Answer:
(d) Both Assertion and Reason are false

VI. Very short Answers

Question 1.
What is a complex tissue?
Answer:
Complex tissue is made up of different types of cells but all the cells perform the same function.

Question 2.
What is a stem cell?
Answer:
It is a cell which is capable of becoming another more differentiated type of cell such as skin cell, nerve cell etc., in the body.

Question 3.
What is ‘white of the eye’?
Answer:
Sclera is called as white of the eye. It is a tough and thick white sheath that protects the inner parts of the eye.

Question 4.
Define diffusion.
Answer:
Diffusion is the movement of particles from an area of higher concentration to lower concentration. The overall effect is to equalize concentration throughout the medium.
Example: Perfume filling a whole room.

Question 5.
Write the equation for aerobic respiration.
Answer:
Glucose + Oxygen → Carbon dioxide + Water + Energy.

VII. Short Answer

Question 1.
What is osmoregulation?
Answer:

1. Osmoregulation is the process by which an organism regulates the water balance in its body and maintains the homeostasis of the body.
2. It includes controlling excess water loss or gain and maintaining the fluid balance and the osmotic concentration, that is, the concentration of electrolytes.
3. It ensures that the fluids in the body do not get too diluted or concentrated

Question 2.
Differentiate aqueous humour and vitreous humour.

Aqueous humour:

• It is a watering fluid.
• It is found between cornea and lens of the eye.

Vitreous humour:

• It is semi – solid, transparent and jelly like.
• It is found between lens and retina of the eye.

Question 3.
What is the signification of ciliated epithelium present in the nostrils?
Answer:

1. The inner surface of nasal cavity is lined with cilia and mucus producing cells, which make it sticky and moist.
2. The cilia and mucus trap dust and germs and prevent them from going deeper into the respiratory tract.

Question 4.
How is connective tissue classified?
Answer:
Connective:

(i) Areolar:

• Tendon
• Ligament

(ii) Adipose:

(iii) Skeletal:

• Bone
• Artilage

(iv) Fluid:

• Blood
• Lymph

VI. Long Answer

Question 1.
Describe the parts in the external structure of the eye.
Answer:
The external Structure of an Eye:
The parts of the eye that are visible externally comprise of the external structure of
the eye.

1. Sclera:
It is a tough and thick white sheath that protects the inner parts of the eye. It is the ‘White of the eye’.

2. Conjunctiva:
It is a thin transparent membrane that is spread across the sclera. It keeps the eyes moist and clear by secreting small amounts of mucus and tears.

3. Cornea:
It is the transparent layer of membrane that is spread over the pupil and the iris. The main role of the cornea is to refract the light that enters the eyes.

4. Iris:
It is a pigmented layer of tissues that make up the colored portion of the eye. Its primary function is to control the size of the pupil, depending on the amount of light entering it.

5. Pupil:
It is the small opening located at the middle of the Iris. It allows light to come in

Question 2.
Draw a neat labelled diagram of human respiratory system.
Answer:

Question 3.
Answer:

1. The lungs are organs in the chest cavity that allow our body to take in oxygen from the air. They also help to remove carbondioxide from the body.
2. The lungs lie on either side of the breast bone and fill the inside of the chest cavity. The left lung is slightly smaller than the right lung to allow room for the heart.
3. Within the lungs, each bronchiole leads to a bunch of air sacs called alveoli (singular : alveolus).
4. The lungs are two spongy elastic bags, on each side of the thoracic cavity.

Alveoli:

• Alveoli are tiny air sacs in the lungs.
• Alveoli are the workhorses of your respiratory system.
• About 480 million alveoli, are located at the end of bronchial tubes.
• Alveoli, is meant for the exchange of oxygen and carbon dioxide takes place.

VII. Creative questions : Hots

Question 1.
Is breathing similar to respiration? Justify.
Answer:
Breathing refers to the physical process of inhalation and exhalation. Respiration is the process by which organisms breakdown glucose into a form that the cells can use as energy

You can Download Samacheer Kalvi 8th Social Science Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Social Science Economics Solutions Term 1 Solutions Chapter 1 Money, Savings and Investments

Samacheer Kalvi 8th Social Science Money, Savings and Investments

I. Choose the correct answer

Money And Banking 8th Class Social Notes Question 1.
Which metals were used for metallic money?
(a) Gold
(b) Silver
(c) Bronze
(d) All the above
Answer:
(d) All the above

8th Standard Economics Question 2.
Who introduced the paper money?
(a) British
(b) Turkish
(c) The Mugual Empire
(d) Mauryas
Answer:
(a) British

Social Money Solutions Question 3.
The value of money is
(a) Internal value of money
(b) External value of money
(c) Both a & b
(d) None of these
Answer:
(c) Both a & b

Money And Credit Class 10 Intext Solutions Question 4.
Which is the Bank Money?
(a) Cheque
(b) Draft
(c) Credit and Debit cards
(d) All the above
Answer:
(a) Cheque

Primary Secondary And Contingent Functions Of Money Question 5.
Pick out the incorrect one:
Investment can be made in different vehicle.
(a) Stock
(b) Bonds
(c) Mutual fund
(d) Pay tax
Answer:
(d) Pay tax

Question 6.
Who is responsible for the collection and publication of monetary and financial information?
(a) Finance commission
(b) Finance Ministry
(c) Reserve Bank of India
(d) Auditor and Comptroller General of India
Answer:
(c) Reserve Bank of India

Fill in the Blanks

1. Online Banking is also known as ……………
2. ……………. is what money does.
3. The term of bank is derived from ……………. word.
4. Value of money is meant …………….. of money.
5. The Indian banking regulation act of ……………..

Answer:

1. Net Banking
2. Money
3. German
4. The purchasing power
5. 1949

III. Match the following

Answer:

1. iv
2. v
3. ii
4. iii
5. i

IV. Write the one word answer

Question 1.
The word Money is derived from?
Answer:
The word Money is derived from Roman word “Moneta Juno”

Question 2.
Which bank gives to both short term and long term loans?
Answer:
Rural cooperative credit institutions.

V. Choose the correct statement

Question 1.
Barter system had many deficiency like –
I. Lack of double coincidence of wants
II. No difficulties of storing wealth
III. Common measure of value
IV. Indivisibility of commodities

(a) I and II is correct
(b) I and IV is correct
(c) I, III and IV is correct
(d) All are correct
Answer:
(c) I, III and IV is correct

VI. Find out the odd one

Question 1.
Recent forms of money transactions are
(a) Credit card
(b) Barter system
(c) Debit card
(d) Online banking
Answer:
(b) Barter system

Question 2.
Effects of black money on economy is
(a) Dual economy
(b) Undermining equity
(c) No effects on production
(d) Lavish consumption spending
Answer:
(c) No effects on production

VII. Write short answer

Question 1.
What is the Barter System?
Answer:
A barter system is an old method of exchange. Barter system is exchanging goods for goods without the use of money in the primitive stage.

Question 2.
What are the recent forms of money?
Answer:
Plastic Money and E – Money

Question 3.
Short note on E – Banking and E – Money.
Answer:
1. E – Money:
Electronic Money is money which exists in banking computer systems and is available for transactions through electronic system.

2. E – Banking:
Electronic banking, also known as National Electronic Funds Transfer (NEFT), is simply the use of electronic means to transfer funds directly from one account to another rather than by cheque or cash.

Question 4.
What are the essential of Money in your life?
Answer:
Money is used as the source to fulfill basics needs as well as comforts in life. It gets people accommodation, clothes, food and other things which add to luxury in life. It is an important source to live a healthy life too.

Question 5.
What is the Value of Money?
Answer:
Value of money is the purchasing power of money over goods and services in a country.

Question 6.
What is the Commercial Bank and its types of Deposits?
Answer:
A bank that offers services to the General public and companies is a commercial banks. The types of deposits in a commercial bank are

1. Time deposits. Example Fixed deposit
2. Recurring deposit and Demand deposit Example Current Account and Savings Account.

Question 7.
What is Savings and Investment?
Answer:

1. Savings represents that part of the person’s income which is not used for consumption
2. Investment refers to the process of investing funds in capital asset, with a view to generate returns

Question 8.
What is meant by Black Money?
Answer:
Black Money is money earned through any illegal activity controlled by country regulations.

Question 9.
What are the effects of black money on economy?
Answer:

1. Dual economy
2. Tax evasion, thereby loss of revenue to government.
3. Undermining equity
4. Widening gap between the rich and poor

VIII. Write Brief answer

Question 1.
What are the disadvantages of barter system?
Answer:

1. Lack of double coincidence of wants,
2. Common measure of value
3. Indivisibility of commodities
4. Difficulties of storing wealth

Question 2.
Write about the evolution of Money.
Answer:
Money has evolved through different stages according to the time, place and circumstances.

1. Commodity Money:
In the earliest period of human civilization, any commodity that was generally demanded and chosen by common consent was used as money. Example Goods like furs, skins, salt, rice, wheat, utensils, weapons etc. Such exchange of goods for goods was known as ‘Barter Exchange’.

2. Metallic Money:
With progress of human civilization, commodity money changed into metallic money. Metals like gold, silver, copper, etc. were used as they could be easily handled. It was the main form of money throughout the major portion of recorded history.

3. Paper Money:
(a) It was found inconvenient as well as dangerous to carry gold and silver coins from place to place. So, invention of paper money marked a very important stage in the development of money.

(b) Paper money is regulated and controlled by Central bank of the country (Reserve Bank of India). At present, a very large part of money consists mainly of currency notes or paper money issued by the central bank.

4. Credit Money or Bank Money:
(a) Emergence of credit money took place almost side by side with that of paper money. Example Cheque.

(b) The cheque (known as credit money or bank money), itself, is not money, but it performs the same as functions of money.

5. Near Money:
The final stage in the evolution of money has been the use of bills of exchange, treasury bills, bonds, debentures, savings certificate etc.

Question 3.
What are the functions of Money? and explain it.
Answer:
Functions of money are classified into Primary or Main function, Secondary function and Contingent function.

Primary or main functions:
The important functions of money performed in very economy are classified under main functions:

1. Medium of exchange or means of payment – Money is used to buy the goods and services.

2. Measure of value – All the values are expressed in terms of money it is easier to determine the rate of exchange between various type of goods and services.

Secondary functions:
The three important of secondary functions are
1. Standard of deferred payment – Money helps the future payments too. A borrower borrowing today places himself under an obligation to pay a specified sum of money on some specified future date.

2. Store of value or store of purchasing power – Savings were discouraged under barter system as some commodities are perishable. The introduction of money has helped to save it for future as it is not perishable.

3. Transfer of value or transfer of purchasing power – Money makes the exchange of goods to distant places as well as abroad possible. It was therefore felt necessary to transfer purchasing power from one place to another.

Contingent functions:

• Basis of credit
• Increase productivity of capital
• Measurement and Distribution of National Income

Question 4.
Explain the types of bank Deposits.
Answer:
1. Student Savings Account:
There are savings accounts some banks offer specifically for young people enrolled in high school or college, and they main feature more flexible terms such as lower minimum balance requirements.

2. Savings Deposits:
Savings deposits are opened by customers to save the part of their current income. The customers can withdraw their money from their accounts when they require it. The bank also gives a small amount of interest to the money in the saving deposits.

3. Current Account Deposit:
Current accounts are generally opened by business firms, traders and public authorities. The current accounts help in frequent banking transactions as they are repayable on demand.

4. Fixed Deposits:
Fixed deposits accounts are meant for investors who want their principle to be safe and yield them fixed yields. The fixed deposits are also called as Term deposit as, normally, they are fixed for specified period.

Question 5.
What are the difference between savings and investment?
Answer:

Question 6.
What are the effects of black money on economy?
Answer:|
Effects of Black Money on economy

1. Dual economy
2. Tax evasion, thereby loss of revenue to government.
3. Undermining equity
4. Widening gap between the rich and poor
5. Lavish consumption spending
6. Distortion of production pattern
7. Distribution of scarce resource
8. Effects on production.

Intext Hots

Question 1.
If there is no invention of money – Imagine.
Answer:
Money is one of the most fundamental inventions of mankind. “Every branch of knowledge has its fundamental discover”. In mechanics, it is the wheel, in science fire, in politics the vote. Similarly in economics, in the whole commercial side of Man’s social existence, money is the essential invention on which all the rest is based.

Intext Activity

Question 1.
Fill up the following Table:
Answer:

Samacheer Kalvi 8th Social Science Economics Money, Savings and Investments Additional Questions

I. Choose the correct answer

Question 1.
‘Rupya’ in Sanskrit mean ……………. coin.
(a) Gold
(b) Silver
(c) Bronze
(d) Copper
Answer:
(b) silver

Question 2.
……………. doesn’t involve money.
(a) Bartering
(b) Net banking
(c) E – banking
(d) Credit card
Answer:
(a) Bartering

Question 3.
The ……………… came up with the Punch Marked Coins minting of silver, gold copper or lead.
(a) Mughals
(b) Kushans
(c) Mauryas
(d) Greeks
Answer:
(c) Mauryas

Question 4.
The …………… Empire from 1526 AD consolidated the monetary system for the entire empire.
(a) Greeks
(b) Turks
(c) Mauryas
(d) Mughals
Answer:
(d) Mughals

Question 5.
The receipts of ………….. were a substitute for money and became paper money.
(a) Bankers
(b) Gold smiths
(c) Carpenters
(d) Zamindars
Answer:
(b) Gold smiths

Question 6.
The symbol of Rupee was approved by the Government of India on ……………..
(a) 15 July 2010
(b) 15 June 2010
(c) 10 July 2011
(d) 12 July 2011
Answer:
(a) 15 July 2010

II. Fill in the blanks

1. …………… of Lydia innovated mental coin the 8th Century BC.
2. …………… kings introduced the Greek custom of engraving portraits on the coins.
3. …………… Sultans of Delhi replaced the royal designs of Indian king with Islamic Calligraph.
4. In the 12th Century AD, the currency made up of gold, silver and copper was known as ……………. and lower valued coin as ……………
5. Silver coin of 178gms issued by Sher Shah Suri was called ……………….
6. ……………. the Mughal Emperor gave permission to the Britishes to coin Mughal money at the Bombay mint.
7. The relation between the value of money and price level is an ……………. one.
8. The Indian Rupee symbol was designed by ……………. of Villupuram district.
9. …………….. has the legal power to discharge debts.
10. The Government of India announced demonitization on ……………..

Answer:

1. Kind Midas
2. Indo – Greek Kushan
3. Turkish
4. Tanka, Jittal
5. Rupiya
6. Farrukhsiyar
7. Inverse
8. Udayakumar
9. Money
10. 8 November 2016

III. Match the following

Answer:

1. iii
2. iv
3. i
4. ii

IV. Choose the correct statement

Question 1.
(i) In November 2016, Government of India announced demonetization of all 100 rupee bank notes
(ii) Demonetization is a step against Black money.
(iii) Prevention of corruption Act was passed in 1988.
(iv) Benami transactions prohibition act 1988 was amended in 2011.

(a) i and ii are correct
(b) ii and iii are correct
(c) iii and iv are correct
(d) i, ii and iii are correct.
Answer:
(b) ii and iii are correct

V. Find the odd one

Question 1.
Investment can be made in
(a) Stock
(b) Bonds
(c) Insurance
(d) Credit card
Answer:
(d) Credit card

VI. Give Short Answers

Question 1.
What is Robertson’s definition of money?
Answer:
Robertson is defined as, “Money is anything which is widely accepted in payment for goods or in discharge of other business obligations”.

Question 2.
Name the stages through which money has evolved.
Answer:
Commodity Money, Metallic Money, Paper Money, Credit Money, Near Money and recent forms of Money.

Question 3.
How were the British coins termed?
Answer:
The British gold coins were termed as Carolina, the silver coins as Angelina, the copper coins as cupperoon and the tin coins as tinny.

Question 4.
What is plastic money?
Answer:
The latest type of money is plastic money in the form of Credit cards and Debit cards. They aim for cashless transactions.

Question 5.
Write a short note on Online banking.
Answer:

1. Online Banking, also known as internet banking is an electronic payment system.
2. It enables customers of a bank or other financial institutions to conduct a range of financial transactions through website.

Question 6.
Mention the types of value of money and describe them.
Answer:
The value of money is of two types

1. Internal value of money
2. External value of money

The Internal value of money refers to the purchasing power of money over domestic goods and services. The External value of money refers to the purchasing power of money over foreign goods and services.

Question 7.
Answer:
Define Inflation and Deflation.

1. Inflation refers to the prices are rising, the value of money will fall.
2. Deflation refers to the prices are falling, the value of money will rise.

Question 8.
State some ways in which investments are made.
Answer:
Investment can be made in different investment vehicles like,

1. Stock
2. Bonds
3. Mutual funds
4. Commodity futures
5. Insurance
6. Annuities
7. Deposit account or any other securities or assets

Question 9.
What is the root cause for the increasing rate of black money in a country?
Answer:
The root cause for the increasing rate of black money in the country is the lack of strict punishments for the offenders.

Question 10.
Brief the recent steps of the Government of India against black money.
Answer:

1. Under pressure from India and other countries, Switzerland has made key changes in its local laws governing assist foreign allegedly stashed in Swiss Banks.
2. Special Investigation Team appointed by government on the directions of Supreme Court on black money.
3. Demonetization

VII. Answer the following

Question 1.
What are the benefits of saving?
Answer:
Benefits of Savings

1. You will be financially independent sooner.
2. You would not have to worry any unforeseen expenses.
3. In future, you will have financial backup in place if you lose your job.
4. You will be prepared if your circumstances change.
5. You will be more comfortable in retirement.
6. Save today for better tomorrow.

You can Download Samacheer Kalvi 8th Social Science Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Samacheer Kalvi 8th Social Science Geography Solutions Term 1 Chapter 1 Rock and Soil

Samacheer Kalvi 8th Social Science Rock and Soil Textbook Evaluation

I. Choose the correct answer

Rock And Soil Class 8 Question 1.
Which of the following is known as sphere of rocks –
(a) Atmosphere
(b) Biosphere
(c) Lithosphere
(d) Hydrosphere
Answer:
(c) Lithosphere

Rocks And Soils 8th Standard Question 2.
World soil day is observed on –
(a) 15th August
(b) 12th January
(c) 15th October
(d) 5th December
Answer:
(d) 5th December

Samacheer Kalvi Guru 8th Social Question 3.
Fossils are found in –
(a) Sedimentary rocks
(b) Igneous rocks
(c) Metamorphic rocks
(d) Plutonic rocks
Answer:
(a) Sedimentary rocks

Social Samacheer Kalvi 8th Question 4.
The first layer of soil is called as –
(a) Regur
(b) Regolith
(c) Unweathered rock
(d) Partially weathered rock
Answer:
(*) Horizon

8th Social Guide Samacheer Kalvi Question 5.
Ideal soil for growing cotton is –
(a) Red soil
(b) Black soil
(c) Alluvial soil
(d) Mountain soil
Answer:
(b) Black soil

Samacheer Kalvi 8th Social Book Question 6.
The major component of soil is –
(a) Rocks
(b) Gas
(C) Water
(d) Minerals
Answer:
(d) Minerals

Samacheer Kalvi Guru 8th Social Science Question 7.
Which one of the following is the most widespread most and’productive category of soil –
(a) Alluvial soil
(b) Black soil
(c) Red soil
(d) Mountain soil
Answer:
(a) Alluvial soil

II. Fill in the Blanks

1. Scientific study of rocks is called ………………
2. …………… soil is highly suitable for cotton cultivation.
3. The “skin of earth” is ……………..
4. ……………. is the kind of metamorphic rock using which Taj Mahal was built.
5. ……………. is known as the primary rocks.

Answer:

1. Petrology
2. Black
3. Soil
4. White Marble
5. Igneous rock

III. State whether the following statements are true or false

Samacheer Kalvi 8th Social Question 1.
Igneous rocks are called primary rocks.
Answer:
True

Samacheer Kalvi 8th Social Science Question 2.
Slate is formed from shale.
Answer:
True

Samacheer Kalvi 8th Books Solutions Social Science Question 3.
Red soil is formed by the process of leaching.
Answer:
False
Correct statement:
Laterites soils i s formed by the process of leaching.

8th Social Samacheer Kalvi Question 4.
M – sand is used as alternative for natural sand in construction.
Answer:
True

Samacheer Kalvi.Guru 8th Social Question 5.
Volcanic mountains are covered with sedimentary rocks.
Answer:
False
Correct statement:
Sedimentary rocks are formed from broken pieces of rocks.

IV. Match the following

Samacheer Kalvi Social Science 8th Question 1.
Answer:

a. 2
b. 1
c.  4
d. 3.

Samacheer Kalvi 8 Social Question 2.

Answer:

a. 2
b. 4
c.  1
d.  3.

V. Choose the incorrect statement from the following

Kalvi Guru 8th Social Question 1.

1. Igneous rocks are called the primary rocks.
2. Soil is the product of weathering of rocks.
3. Sedimentary rocks are the hardest ones.
4. Deccan plateau is the region of Igneous rocks.

Answer:
3. Sedimentary rocks are the hardest ones.

8th Samacheer Kalvi Social Question 2.

1. Soil erosion decreases its fertility.
2. Dynamic metamorphism is caused by high temperature.
3. Soil is a renewable source.
4. Humus is a part of the top layer of soil.

Answer:
2. Dynamic metamorphism is caused by high temperature.

VI. Consider the following statements and choose the right option from the given ones

Statement (1) – Sedimentary rocks consist of many layers.
Statement (2) – Sedimentary rocks are formed by the sediments deposited at different points of time.

1. 1 and 2 are correct and 2 explains 1
2. 1 and 2 are correct but, 2 does not explain 1
3. 1 is correct but, 2 is incorrect
4. 2 is correct but, 1 is incorrect.

Answer:
1. 1 and 2 are correct and 2 explains 1

VII. Give reasons for the following

Social Guide For Class 8 Samacheer Kalvi Question 1.
Chemical sedimentary rocks are found in the beds of reservoirs.
Answer:
Chemical Sedimentary rocks are formed by precipitating of minerals from water. It is formed usually through evaporation of chemical rich solutions.

Samacheer Kalvi Guru 8 Social Science Question 2.
Igneous rocks are found in the regions of volcanoes.
Answer:
The igneous rocks are formed by the solidification of molten magma.

VIII. Distinguish the following

Samacheer Kalvi 8th Books Social Science Question 1.
Metamorphic rock and sedimentary rock.
Answer:

Metamorphic Rocks:

• Formed when Igneous and Sedimentary rocks are subjected to high temperature and pressure.
• Mostly crystalline in nature
• Fossils donot survive in these rocks
• Example Gneiss, Slate, quartz

Sedimentary Rocks:

• Formed by the sediments derived and deposited by various agents.
• They are non – crystalline rocks
• Contain fossils., Example Coal, Oil, natural gas
• Example Chalk, Sandstone, Rock Salt

Question 2.
Soil conservation and Soil erosion.
Answer:

Soil conservation:

• The process of protecting the soil from erosion to maintain its fertility.
• Methods of soil conservation are afforestation, controlled grazing, construction of dams, crop rotation etc.,

Soil erosion:

• Removal or destruction of the top layer of soil by natural forces and human activities.
• Running water and wind are the major agents of Soil erosion.
  Rill erosion and Gully erosion are the major types of soil erosion

IX. Give short answers

Question 1.
How are igneous rocks formed?
Answer:
The igneous rocks are formed by the solidification of molten magma.

Question 2.
Describe about the composition of soil.
Answer:
The basic components of soil are mineral, organic matter, water and air. It consists of about 45% mineral, 5% organic matter, 25%  of water and 25% air. It is only a generalized fact. The composition of soil varies from place to place and time to time.

Question 3.
Define ‘rock’.
Answer:

1. The rocks are the solid mineral materials forming a part of the surface of the earth and other similar planets.
2. A rock is an aggregate of one or more minerals. Rock is an important natural resource and is found in solid state.
3. It may be hard or soft in nature.

Question 4.
State the types of soils.
Answer:
Alluvial soil, Black soil, Red soil, Laterite soil, Mountain soil, Desert soil.

Question 5.
What is soil conservation?
Answer:
Soil conservation is the process of protecting the soil from erosion to maintain its fertility.

X. Give detailed answer for the following

Question 1.
Explain the process of soil formation.
Answer:

1. Soil is a mixture of organic matter, minerals, gases, liquids and organisms that together support life.
2. Soil minerals form the basis of soil. It forms on the surface of the earth. It is known as the ‘skin of the earth’.
3. Soils are produced from rocks (parent material) through the processes of weathering and natural erosion.
4. Water, wind, temperature change, gravity, chemical interaction, living organisms and pressure differences all help break down parent material. It leads to the formation of loose material.
5. In course of time, they further break down into fine particles. This process release the minerals locked in the rock fragments.
6. Later on, the vegetative cover which develop in that region forms humus content in the soil. This way the soil gets matured gradually.

Question 2.
Classify and explain the rocks.
Answer:

Igneous:
(i) The igneous rocks are formed by the solidification of molten magma. Also called Primary or Parent Rocks.
(ii) Types:

• Extrusive Igneous Rocks.
• Intrusive Igneous Rocks

1. Extrusive Igneous Rocks:
Molten magma which comes out from the interior of the earth’s surface, gets solidified and forms such rocks. Fine grained and glassy in nature. Eg., Basalt, found in north western peninsular India.

2. Intrusive Igneous rocks:
Molten magma cools down deep inside the earth’s crust, becomes solid and forms such rocks. Form large grains. Deep seated rocks are plutonic rock and ones at shallow depths – Hypabysal rocks. Example Granite, Diorite.

Sedimentary:
(i) Formed by the sediments derived and deposited by various agents. Also called stratified rocks.
(ii) Types:

• Organic sedimentary rocks
• Mechanical sedimentary rocks,
• Chemical sedimentary rocks

1. Organic sedimentary rocks:
Formed due to decomposition of dead Plants and Animals. Contains fossils. Example Chalk, Talc

2. Mechanical sedimentary rocks:
Formed from the disintegration of Igneous and metamorphic rocks. Get deposited due to erosion by natural agents. Get cemented after a long time to form rocks. Example Sandstone, Shale.

3. Chemical sedimentary rocks: Formed by precipitating of minerals from water. Formed due to evaporation of chemical rich solution. Example Rock Salt.

Metamorphic:
(i) Formed when Igneous and sedimentary rocks are subjected to high temperature and pressure.
(ii) Types:

• Thermal
• Dynamic

1. Thermal Metamorphic:
If the change in rocks is caused by high temperature.

2. Dynamic Metamorphic:
If the change in rock is caused by high pressure. Formed from Igneous rocks. Eg., Granite into gneiss
Formed from Sedimentary rocks. Eg., Shale into Slate

Question 3.
Give an account on different layers of soil.
Answer:

Question 4.
Classify and explain the soil.
Answer:
Definition:
Soil is a mixture of Organic matter, minerals, gases, liquids and organisms that together support life.

Classification of soils:
Soils are classified on the basis of their formation, colour, physical and chemical properties. Based on these, soil is classified into six major types. They are: Alluvial soil, Black soil, Red soil, Laterite soil, Mountain soil, Desert soil.

Alluvial soil:

• Found in the regions of river valleys, flood plains and coastal regions.
• Formed by the deposition of silt by the running water.
• Most productive of all soils.
• Suitable for the culitivation of sugarcane, jute, rice, wheat.

Black soils:

• Formed by weathering of igneous rocks.
• Clayey in nature.
• Retains moisture.
• Ideal for growing cotton.

Red Soils:

• Formed by weathering of metamorphic rocks and crystalline rocks.
• Found in semi – arid regions.
• Not a fertile.
• Is soil brown red in colour due to the presence of iron oxide
• Suitable for millet cultivation.

Laterite soils:

• Formed by the process of leaching.
• Found in trophical regions, which experienced alternate wet and dry condition.
• Infertile soil.
• Suitable for plantation of tea and coffee.

Mountain soils:

• Found in slopes of mountains.
• Thin and acidic in nature.
• Nature of soil differs based on the altitude.

Desert soils:

• Found in hot desert region.
• Porous and saline in nature.
• Infertile in nature.
• Agriculture not successful.

IX. Activity Corner

Question 1.
Complete the following table with the help of internet source

Answer:

Question 2.
Map Work:
Mark the areas of black soil on the outline map of India.
Answer:

Samacheer Kalvi 8th Social Science Geography Rock and Soil Additional Questions

I. Choose the correct answer

Question 1.
……………. rocks are also called Primary rocks.
(a) Sedimentary
(b) Igneous
(c) Metamorphic
(d) Stratified
Answer:
(b) Igneous

Question 2.
…………….. rocks are also known as stratified rocks.
(a) Igneous
(b) Metamorphic
(c) Sedimentary
(d) Hypabysal
Answer:
(c) Sedimentary

Question 3.
Oldest sedimentary rocks of the world have been identified in
(a) Green land
(b) India
(c) France
(d) Australia
Answer:
(a) Creen landi

Question 4.
…………….. soil is suitable for milled cultivation.
(a) Alluvial
(b) Black
(c) Latente
(d) Red
Answer:
(d) Red

Question 5.
……………. soil is porous and saline.
(a) Mountain
(b) Desert
(c) Alluvial
(d) Red
Answer:
(b) Deserti

Question 6.
The time needed to form soil depends on the ……………..
(a) altitude
(b) rainfall
(c) climate
(d) fertility
Answer:
(c) climate

II. Fill in the blanks

1. ……………. refer to rock in Greek.
2. Out of 2,000 different types, only ……………. are the basic minerals commonly found all over the earth.
3. ……………. are chemical substances which exist in nature.
4. Minerals exist in nature ¡n the form of ……………. or …………..
5. The world Igneous is derived from the Latin word ……………. meaning …………….
6. Intrusive Igneous rocks are also called ………….. rocks.
7. Meta means ………….. and morpha means ………………
8. In wet tropical area soil formation is ………………

Answer:

1. Petrus
2. 12
3. Minerals
4. Elements, compounds
5. Ignus, firel
6. Crystallins
7. Change, shape
8. Faster

III. Match the following

a. iiii
b. iv
c. i
d. ii

IV. Choose the incorrect statement from the following

Question 1.

1. Igneous rocks donot contain fossils
2. The oldest sedimentary rock in the world is 3.9 billion years old.
3. Soil consists of 5% Organic matter.
4. Laterite soil is thin and acidic.

Answer:
4. Laterite soil is thin and acidic

V. Consider the following statement and choose the right option from the given ones

Question 1.
Statement (1) :
Proper management of soil resource will lead to sustainable food production.

Statement (2) :
India is an Agricultural country.

1. 1 and 2 are correct but 2 does not explain.
2. 1 is correct but 2 is incorrect.
3. 1 and 2 are correct and 2 explains 1.
4. 1 is incorrect but 2 is correct.

Answer:
3. 1 and 2 are correct and 2 explains 1

VI. Give Reason for the following

Question 1.
The Laterite soil is infertile.
Answer:
Laterite are the typical soils of trophical regions. These soils are found in the regions which experienced alternate wet and dry condition. As these soils are formed by the process of leaching, it is in fertile.

Question 2.
Sedimentary rocks are called stratified rocks.
Answer:
Sedimentary rocks consist of many layers which were formed by the sediments deposited at different periods. As it consists of many strata, it is also known as ‘Stratified rocks’.

VII. Distinguish the following

Question 1.
Igneous rock and sedimentary rock.
Answer:

Igneous rocks:

• Formed by the solidification of molten magma.
• Classified into 2 types:
• Extrusive and Intrusive Igneous rocks.
• Crystalline in nature.
• Hard in nature.

Sedimentary rocks:

• Formed by the sediments derived and deposited by various agents.
• Classified into 3 types:
• Organic, Mechanical, Chemical sedimentary rocks.
• Non – crystalline rocks
• Soft and get eroded easily.

VIII. Give short answers

Question 1.
Name the four realms of earth.
Answer:
Four realms of the earth, are lithosphere, hydrosphere, atmosphere and biosphere.

Question 2.
What is the Lithosphere composed of?
Answer:
Lithosphere is composed of solid rocks and unconsolidated materials.

Question 3.
What is lava?
Answer:
Lava is actually a fiery red molten magma comes out from the interior of the earth on its surface.

Question 4.
Why are crystalline rocks called so?
Answer:
The intrusive Igneous rocks consist of large crystals, and so they are also called as ‘Crystalline rocks’.

Question 5.
Name a few Major Active Volcanoes.
Answer:
Major Active Volcanoes:
Mount Vesuvius, Mt. Stromboli and Mt. Etna in Italy and Mauna Loa and Mauna Kea in Hawaii Islands.

Question 6.
What are the characteristics of Sedimentary rocks?
Answer:

1. They have many layers.
2. They are non-crystalline rocks.
3. They contain fossils.
4. They are soft and get eroded easily.

Question 7.
What is Thermal Metamorphism?
Answer:
If the change in the rocks is mainly caused by high temperature, the process is called as thermal metamorphism..

Question 8.
Explain Dynamic Metamorphism.
Answer:
If the change in the rock is mainly caused by high pressure, the process is called as Dynamic Metamorphism.

Question 9.
State the characteristics of Metamorphic rocks.
Answer:

1. Metamorphic rocks are mostly crystalline in nature.
2. They consist of alternate bands of light and dark minerals.

Question 10.
Mention some uses of rocks.
Answer:

1. Cement
2. Writing chalk
3. Fire
4. Building materials
5. Bath scrub
6. Kerb stone
7. Ornament
8. Roofing materials
9. Decorative materials
10. These are valuable source of minerals such as gold, diamond, sapphire etc.

IX. Give Detailed Answer

Question 1.
Explain the different types of sedimentary rocks.
Answer:
Types of Sedimentary Rocks
1. Organic Sedimentary Rocks:

• These rocks are formed as a result of the decomposition of dead plants and animals.
• It contains fossils. Chalk, Talc, Dolomite and Limestone rocks are of this category.

2. Mechanical Sedimentary Rocks:

• These rocks are formed from the disintegration of igneous and metamorphic rocks.
• The natural agents erode and transport these rocks and deposit them at some places. After a long period of time, they cemented to form rocks.
• Sandstone, Shale and Clay are the examples of rocks of this type.

3. Chemical Sedimentary rocks

• These are formed by precipitating of minerals from water. It is formed usually through evaporation of chemical rich solutions.
• These rocks are also called as evaporates.
• Rock Salt is an example of this kind.

Question 2.
Explain the Rock cycle with a diagram.
Answer:
1. Igneous rocks are the primary rocks formed first on the earth. These rocks are weathered, eroded, transported and deposited at some places to form sedimentary rocks.

2. The Igneous and Sedimentary rocks are changed into metamorphic rocks under the influence of temperature and pressure.

3. The metamorphic rocks are also get disintegrated and deposited to form sedimentary rocks.

4. Formation of igneous rocks take place when there is an outflow of molten materials. Like this, the rocks of the earth crust keeps on changing from one form to another form under various natural forces and agents.

5. The endless process is referred as Rock Cycle.

Question 3.
Mention the uses of soils.
Answer:
Uses of soils:
Soil is one of the important natural resource. It is a basic requirement for plant growth and supports various life forms on the earth.

1. The minerals present in the soil enhance and nourishes the crops and plants.
2. It is used in making of ceramics or pottery.
3. It is a source of material for construction and handicraft works.
4. It acts as natural filter of water and purifies it.
5. Soil supports ecosystem and play an important role in land management.

You can Download Samacheer Kalvi 8th Science Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Science Solutions Term 1 Chapter 6 Micro Organisms

Samacheer Kalvi 8th Science Solutions Micro Organisms Text Book Exercises

I. Multiple choice questions

8th Science Microorganisms Book Back Answers Question 1.
Micro organisms are measured in ……………..
(a) cm
(b) mm
(c) micron
(d) meter.
Answer:
(c) micron

8th Science Microorganisms Question Answer Question 2.
Shows both living and non-living characteristics ………………
(a) Protozoa
(b) Virus
(c) Bacteria
(d) Fungi
Answer:
(b) Virus

Samacheer Kalvi Guru 8th Science Question 3.
……………. is a prokaryotic micro organisms.
(a) Virus
(b) Algae
(c) Fungi
(d) Bacteria
Answer:
(d) Bacteria

Samacheer Kalvi Guru 8th Science Solutions Question 4.
Based on shape, the bacteria are classified into …………….. types.
(a) 2
(b) 3
(c) 4
(d) 5
Answer:
(c) 4

Samacheer Kalvi 8th Books Solutions Science Question 5.
The plant body of algae is called as ………………
(a) Stem
(b) Thallus
(c) Leaf
(d) Root
Answer:
(b) Thallus

II. Fill in the blanks

1. ……………… is prepared from a mould called Penicillium.
2. ……………… are the infectious protein particles.
3. The infect virus particle found outside the host cell is ………………
4. Micro organism can be seen with the help of a ………………
5. Bacteria, which have a flagellum at one end is classified as ………………

Answer:

1. Penicillin
2. Prions
3. Virion
4. Microscope
5. Monotrichous

III. Match the following

Samacheer Kalvi 8th Science Question 1.

Answer:

1. e
2. d
3. b
4. c
5. a

III. True or False

Samacheer Kalvi 8th Standard Science Question 1.
Diseases causing micro organisms are called pathogens.
Answer:
True.

8th Standard Samacheer Kalvi Science Question 2.
Female Anopheles mosquito is a carrier of dengue virus.
Answer:
False.
Correct statement:
Female Anopheles mosquito is a carrier of malaria.

Samacheer Kalvi 8th Science Book Question 3.
Chicken pox is a communicable disease.
Answer:
True.

Class 8 Science Samacheer Kalvi Question 4.
Citrus canker is transmitted by insects.
Answer:
True.
Correct statement:
Citrus canker is transmitted by air and water

Samacheer Kalvi 8th Science Book Answers Question 5.
Yeast is used in the large scale production of alcohol.
Answer:
True.

V. Assertion & Reason

Direction:
In each of the following questions, a statement of Assertion is given and a corresponding statement of Reason is given just below it. Of the four statements, given below, mark one as the correct answer.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true and Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If both Assertion and Reason are false.

8th Standard Science Samacheer Kalvi Question 1.
Assertion : Malaria is caused by Protozoa.
Reason : The disease is transmitted by mosquito.
Answer:
(a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion

Science Book Class 8 Samacheer Kalvi Question 2.
Assertion : Algae are heterotrophic.
Reason : They don’t have chlorophyll.
Answer:
(d) Both Assertion and Reason are false

VI. Very short answer type

8th Samacheer Kalvi Science Question 1.
Write the name of any nitrogen fixing bacteria.
Answer:
Rhizobium.

Samacheer Kalvi Science 8th Standard Question 2.
Name the bacteria used in the production of vinegar.
Answer:
Acetobacter aceti.

Science 8th Samacheer Kalvi Question 3.
Write the names of any three protozoans.
Answer:

1. Amoeba
2. Plasmodium
3. Paramecium.

8th Science Samacheer Kalvi Question 4.
Who discovered penicillin?
Answer:
Alexander Flemming.

Samacheer Kalvi Science 8th Question 5.
Which diseases can be prevented by vaccination?
Answer:
Small pox, polio, measles, mumps, rubella, tuberculosis.

VII. Short answer type

Samacheer Kalvi Guru 8th Standard Science Question 1.
Write the four types of bacteria, based on their shape.
Answer:
Bacteria are described according to the shape of their cells. They are:

1. Bacilli – Rod shaped bacteria.
2. Spirilla – Spiral shaped bacteria.
3. Cocci – Spherical or ball shaped bacteria.
4. Vibrio – Comma shaped bacteria.

Kalvi Guru 8th Science Question 2.
What are antibiotics?
Answer:
Antibiotic is a substance produced by living organisms which is toxic for other organisms. Example: Penicillin.

Samacheer Kalvi 8th Books Science Question 3.
What are pathogens?
Answer:
Disease causing organisms are called pathogens. Example: The bacterium Mycobacterium tuberculosis causes tuberculosis in human beings.

Samacheerkalvi.Guru 8th Science Question 4.
How diseases causing micro organisms enter into human beings?
Answer:
The disease causing microbes are called pathogens. They enter into the body through –

1. Cuts and wounds in the skin, mouth or nose.
2. Some pathogens are found in air and enter into a healthy person by breathing. When a patient sneezes, droplets containing microbes spread in air. Example: Tuberculosis, Flu.
3. Some pathogens enter into our body through food and water contaminated with the pathogen. Example: Cholera.
4. Pathogens also enter through blood transfusion from a infected to healthy person. Example: Aids

Samacheer Kalvi.Guru 8th Science Question 5.
Why micro organisms are essential for agriculture?
Answer:
Role of microbes in agriculture:
1. Natural fertilizer:
Microbes like bacteria, fungi act as decomposers and break down the dead and degradable waste of plants and animals. During this process nutrients are released into the soil and the soil becomes fertile. This compost is called natural fertilizer.

2. Nitrogen fixation:
Microbes can fix atmospheric gaseous nitrogen as nitrate salts in the soil. Example: Rhizobium (root nodule bacteria in leguminous plants). Free living bacteria, cyanobacteria (Nostoc).

3. Biocontrol agents:
Microbes act as natural biocontrol agents and protect crops from pests. Example: Baculoviruses attack insects which harm the plants.

VIII. Long answer type

Question 1.
Write a short note on bacteria and its structure.
Answer:
1. Bacteria are single – celled prokaryotes (cells without nuclei).

2. Bacteria are grouped under the kingdom Monera. The study of Bacteria is called Bacteriology.

3. Bacteria are of two types based on respiration

• Aerobic bacteria (requires oxygen).
• Anaerobjc bacteria (Does not requires oxygen).

4. A bacterium has an outer covering known as the cell wall. Nuclear material is represented by a nucleoid without nuclear membrane.

5. An extra chromosomal DNA called plasmid is present in the cytoplasm.

6. Protein synthesis is carried out by 70S ribosomes. Other cell organelles (mitochondria, Golgi body endoplasmic reticulum etc.,) are absent. Flagella aids in locomotion.

7. Bacteria are described according to the shape of their cells. They are:

• Bacilli – Rod shape bacteria
• Spirilla – Spiral shaped bacteria
• Cocci – Spherical or ball shaped bacteria
• Vibrio – Comma shaped bacteria

Bacteria are also classified according to number and arrangement of flagella as follows:

• Monotrichous – Single flagella at one end. Example: Vibrio cholera
• Lophotrichous – Tuft of flagella at one end. Example: Pseudomonas.
• Amphitrichous – Tuft of flagella at both ends. Example:Rhodospirillum rubrum.
• Peritrichous – Flagella all around. Example: E.coli.
• Atrichous – Without any flagella. Example: Corynebacterium diptherae.

Question 2.
How micro organisms are useful in the field of medicine?
Answer:
Role of microbes in medicine:
We obtain antibiotics and vaccines from microbes.

1. Antibiotics:
It is a substance produced by living organisms which is toxic to other organisms. The antibiotic penicillin got from the fungus Penicillium chrysogenum is used to treat diseases like tetanus, diphtheria. Streptomycin got from streptomyces bacteria is used to cure bacterial infections like plague.

2. Vaccines:
They are prepared from dead or weakened microbes. When a vaccine is injected into the body of a patient, it produces antibodies to fight the germs. These antibodies protect the body from infections in future. Example: MMR vaccine for measles.

Question 3.
Answer:

Question 4.
How can we improve the beneficial bacterial count in human beings?
Answer:
We can improve the beneficial bacterial count in human beings by adopting the following methods:

1. Intake of fibre rich foods.
2. Intake of seasonal fruits and vegetables.
3. Intake of plenty of fermented foods with live microbes. Eat more of prebiotic foods.
4. Intake of whole grains.
5. Prefer plant based diet.
6. Avoid artificial sweeteners.

Question 5.
Write a short note on Probiotics.
Answer:
Probiotics:
Probiotics are live food supplements used in yoghurt and other fermented milk products. Example: Lactobacillus acidophilus and Bifidobacterium bifidum. These bacteria improve the microbial spectrum in the gut and thus contribute to the following effects:

1. Decrease the risk of colon cancer
2. Decrease cholesterol absorption
3. Prevent diarrheal diseases by increasing the immunity power.

Samacheer Kalvi 8th Science Solutions Micro Organisms Additional Questions

I. Choose the correct answer

Question 1.
……………. is absent in bacteria.
(a) DNA
(b) RNA
(c) Mitochondria
(d) Cell wall
Answer:
(c) Mitochondria

Question 2.
……………. is not a shape seen in bacteria.
(a) Spiral
(b) Rod shaped
(c) Spherical
(d) Tadpole
Answer:
(d) Tadpole

Question 3.
E.coli is an example of ……………. bacteria.
(a) Peritrichous
(b) Atrichous
(c) Lophotrichous
(d) Monotrichous
Answer:
(a) peritrichous

Question 4.
……………. is not a fungus.
(a) Agaricus
(b) Nostoc
(c) Penicillium
(d) Albugo
Answer:
(b) Nostoc

Question 5
‘Grass of water’ refers to …………….
(a) Fungi
(b) Bacteria
(c) Algae
(d) Bryophytes
Answer:
(c) Algae

Question 6.
……………. is a biocontrol agent.
(a) Mycorrhizae
(b) Rhizobium
(c) Trichoderma
(d) Agaricus
Answer:
(c) Trichoderma

II. Fill in the Blanks

1. One word virus means …………… in Latin.
2. …………… are considered to be the first living organisms on earth.
3. The nuclear material of bacteria is called …………….
4. The extra chromosomal DNA in bacteria is called ……………
5. …………… is a unicellular fungus.
6. The study of fungi is called ……………
7. Yeast has an enzyme called ……………
8. The mode of respiration in yeast is ……………

Answer:

1. Poison
2. Bacteria
3. Nucleoid
4. Plasmid
5. Yeast
6. Mycology
7. Zymase
8. Anaerobic

III. True or False – if false give the correct statement

Question 1.
Agaricus is a biocontrol agent.
Answer:
False.
Correct statement:
Trichoderma is a biocontrol agents.

Question 2.
Nostoc is used for fixing nitrogen.
Answer:
True.

Question 3.
Phycoerythirin is a blue pigment.
Answer:
False.
Correct statement:
Phycoerythrin is a red pigment.

Question 4.
Mushroom is the part of the fungus which produces spores.
Answer:
True.

Question 5.
Plasmodium is a parasite.
Answer:
True.

IV. Match the following

Question 1.

Answer:

i. c
ii. d
iii. a
iv. b

Question 2.

Answer:

i. d
ii. a
iii. b
iv. c

V. Assertion and Reason

Direction:
In each of the following questions, a statement of Assertion is given and a corresponding statement of Reason is given just below it. Of the four statements, given below, mark one as the correct answer.
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true and Reason is not the correct explanation of Assertion.
(c) If Assertion is true but Reason is false.
(d) If both Assertion and Reason are false.

Question 1.
Assertion (A) : Fungi are heterotrophic in nutrition.
Reason (R) : They lack chlorophyll.
Answer:
(a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion

Question 2.
Assertion (A) : Boiling milk is a method of preservation.
Reason (R) : Probiotics is a method of preserving milk.
Answer:
(c) Assertion is true but Reason is false

VI. Very short Answers

Question 1.
What is a plasmid?
Answer:
Extra chromosomal DNA present in bacteria is called plasmid.

Question 2.
Why is nuclear content of a bacterial cell called nucleoid?
Answer:
The nuclear content of a bacterial cell lacks nuclear membrane. So it is called nucleoid.

Question 3.
What are chemosynthetic bacteria?
Answer:
Bacteria that live in harsh environment use chemicals (Ammonia, hydrogen sulphide) to produce their food instead of utilizing energy from the sun. This process is called chemosynthesis.

Question 4.
Why does yeast help in fermentation?
Answer:
It respires anaerobically and has an enzyme called zymase to bring about fermentation.

Question 5.
Name the pigments found in algae.
Answer:
Chlorophylls, fucoxanthin (brown), xanthophylls (yellow), phycoerythrin (red) phycocyanin (blue).

Question 6.
What is biocontrol?
Answer:
Use of microbes to protect crops is called biocontrol.
Example : Trichoderma (fungi) protects plant roots from pathogens.

Question 7.
What is pasteurization?
Answer:

1. Milk is heated up to 70°c to kill the bacteria and it is cooled to 10°c to prevent the growth of remaining bacteria.
2. Then milk is stored in sterilized bottles in cold places.
3. It is a method of preserving milk.

VII. Short Answer

Question 1.
Mention two living characteristics of viruses.
Answer:

1. They respond to heat, chemicals and radiations.
2. They reproduce inside the host cells and produce copies of themselves.

Question 2.
Mention two non living characteristics of viruses.
Answer:

1. They are inactive when present freely in the environment.
2. They can be crystallized and stored for a very long time, like other non – living things.

Question 3.
Draw a diagram of a bacteriophage and label the parts.
Answer:

Question 4.
How are protozoans classified?
Answer:

1. Ciliates – presence of cilia for locomotion (e.g. Paramecium)
2. Flagellates – presence of flagella for locomotion (e.g. Euglena)
3. Pseudopods – presence of pseudopodia for locomotion (e.g. Amoeba)
4. Sporozoans – parasites (e.g. Plasmodium)

Question 5.
What is pseudopodia?
Answer:
In amoeba pseudopodia are the extended part of cell membrane. It helps to catch its prey (algae).

Question 6.
What is retting?
Answer:
Flax plants are tied in bundles and kept in water. Bacteria loosen the supporting fibres of the stem by acting on the stem tissues. This process is known as retting.

Question 7.
Mention the symptoms and preventive measures undertaken for foot and mouth disease in animals.
Answer:

Question 8.
Draw a virion and label the parts.
Answer:

VIII. Long Answer

Question 1.
How are microbes useful in industry?
Answer:
1. Sewage Treatment:
Aerobic microbes are allowed to grow in the primary effluent during the secondary stage of waste water treatment. These microbes consume the major part of the organic matter in the effluent example Nitrobacter sps. In the anaerobic treatment of sewage Methanobacterium is used.

2. Production of Biogas:
Human and animal faecal matter and plant wastes are broken down by anaerobic bacteria to produce methane (biogas) along with carbon dioxide and hydrogen. These bacteria are called as methanogens.

3. Production of Alcohol and Wine:
Alcoholic drinks are prepared by fermentation process using yeast. Sugars in grapes are fermented by using yeast. Beer is produced by the fermentation of sugars in rice and barley.

4. Microbes in Retting and Tanning Process:
1. Retting:
Flax plants are tied in bundles and kept in water. Bacteria loosen the supporting fibres of the stem by acting on the stem tissues. This process is known as retting. Linen thread is made from these fibres example Pseudomonas aeruginosa.

2. Tanning:
In Tanning industry bacteria act upon the skin of animals and makes it soft and therefore it becomes pliable.

Question 2.
Describe the structure of chlamydomonas with neat labelled diagram.
Answer:

1. Chlamydomonas is a simple, unicellular, motile fresh water algae. They are oval, spherical or pyriform in shape.
2. The cell is surrounded by a thin and firm cell wall made of cellulose.
3. The cytoplasm is seen in between the cell membrane and the chloroplast.
4. The cell contains large dark nucleus lying inside the cavity of the cup shaped chloroplast.
5. The anterior part of the cell bears two flagella which helps in locomotion.
6. Two contractile vacuoles are seen at the base of each flagellum.
7. The anterior side of the chloroplast contains a tiny red coloured eyespot.