Question

Short / Long answer type questions.
Write short notes on:
(a) Biological significance of lipids (b) Maltose
(c) Purines and pyrimidines (d) Peptide bond
(e) Glycosidic linkage (f) Asymmetric carbon atom

Answer 1

a)The lipids of physiological importance for humans serve as structural components of biological membranes; provide energy reserves, predominantly in the form of triglycerides, serve as biologically active molecules exerting a wide range of regulatory functions.

b)Maltose is an important intermediate in the digestion of starch. Starch is used by plants as a way to store glucose.

c)Purines and Pyrimidines are nitrogenous bases that make up the two different kinds of nucleotide bases in DNA and RNA. The two-carbon nitrogen ring bases (adenine and guanine) are purines, while the one-carbon nitrogen ring bases (thymine and cytosine) are pyrimidines.

d)A peptide bond is a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O). Helps in the attachment of amino acids.

e) a glycosidic bond or glycosidic linkage is a type of covalent bond that joins a carbohydrate (sugar) molecule to another group, which may or may not be another carbohydrate.

f)Carbon atom which is attached to 4 different groups is called a chiral carbon atom. It is asymmetric and also optically active as it can rotate the plane of polarised light.