Tamilnadu Samacheer Kalvi 12th Chemistry Notes Chapter 15 Chemistry in Everyday Life Notes
Drug: The word drug is derived from the French word “drogue” meaning “dry herb”. A drug is a substance that is used to modify or explore physiological systems or pathological states for the benefit of the recipient. It is used for the purpose of diagnosis, prevention, cure / relief of a disease.
Drug targets: The drug molecule interacts with biomolecules such as enzymes, receptors etc., which are refered as drug targets.
Antagonists: A drug that binds to the receptor site should inhibit its natural function. Such drugs are called antagonists.
Agonists: A drug which mimic the natural messenger by switching on the receptor. These types of drugs are called agonists.
Tranquilizers: They are neurologically active drugs. They acts on the central nervous system by blocking the neuro transmitter dopamine in the brain.
Analgesics: Analgesics are the compounds which relieve all sorts of pains without the loss of consciousness. These are also called pain killer or pain relievers.
Antipyretics: Antipyretics are the compounds which are used for the purpose of reducing fever (lowering the body temperature to the normal)
Anaesthetics: The drugs which produce loss of sensation are called anaesthetics. They are two types (i) General anaesthetics and (it) Local anaesthetics.
Antacids: Certain drugs provide relief from burning sensation. These are known as antacids.
Antihistamines: The drugs which interfere with the natural action of histamines and prevent the allergic reaction.
Antimicrobials: They tend to prevent or destroy or inhibit the pathogenic action of microbes such as bacteria, viruses, fungi etc.
Antiseptics: Drug which either kill or inhibit the growth of micro organisms.
Antifertility drugs: These are the chemical substances used to control pregnancy. They are also called contraceptives or birth control pills.
Food additives: The substances which are not naturally a part of the food and added to improve the quality of the food are called food additives.
Advantages of food additives: (i) Uses of preservatives reduce the product spoilage and extend the shelf-life of food, (ii) Addition of vitamins and minerals reduces the mall nutrient, (iii) Flavouring agents enhance the aroma of the food.(iv) Antioxidants prevent the formation of potentially toxic oxidation products of lipids and other food constituents.
Preservatives: Preservatives are capable of inhibiting retarding or arresting the process of fermentation acidification or other decomposition of food by growth of mirco organisms.
Antioxidants: Antioxidants are substances which retard the oxidative deteriorations of food.
Sugar substituents: Those compounds that are used like sugars for sweetening, but are metabolised without the influence of insulin are called sugar substituents.
Artificial sweetening agents: Synthetic compounds which imprint a sweet sensation and possess no or negligible nutritional value are called artificial sweeteners.
Soaps: Sodium or potassium salt of a long chain fatty acid is called a soap.
Total fatty matter: It is defined as the total amount of fatty matter that can be separated from a sample after splitting with mineral acids. Higher the TFM quantity in the soap better is its quality.
Detergents: Synthetic detergents are formulated products containing either sodium salts of alkyl hydrogen sulphates or sodium salts of long chain alkyl benzene sulphuric acids.
Polymers: They are macromolecules of high molecular masses formed by combination of a large number of simple molecules.
Addition polymers: In these polymers, monomer units are added to form long chains without the elimination of any by product.
Condensation polymers: In these polymers, monomer units are added to form long chains, with the elimination of some by product.
Copolymers: They are formed by the polymerisation of two or more types of monomers.
Natural polymers: They are formed in nature by plants.
Synthetic polymers: They are formed artificially by using certain chemical compounds.
Cross-linked polymers: In these polymers, monomer units are linked to give a three dimensional solid network with cross-linking.
Vulcanization: The properties of natural rubber can be modified by the process called vulcanization. On vulcanization, sulphur form cross links at reactive sites or double bonds and thus the rubber gets stiffened.
Biodegradable polymers: Polymers which disintegrate by themselves over a period of time due to environmental degradation by bacteria or other micro organism are called bio degradable polymers.
Types of detergents: There are three types of detergents, (i) Anionic detergents (ii) cationic detergenets (iii) non-ionic detergents.