Biomolecules: NEET PYQs and weightage

Glycogen is the storage carbohydrate of animals. Globulins are involved in defense mechanisms of the body. An antibody, also known as an immunoglobulin. Steroids are lipids as they are hydrophobic and insoluble in water. Many hormones in the human body are steroids. For example: Progesterone, Testosterone stc. Thrombin is an enzyme in coagulation cascade, which converts inactive fibrinogens of the plasma into fibrins.

Some lipids have phosphorus and a phosphorylated organic compound in them. These are phospholipids. Example - Lecithin found in cell membranes is phospholipid and not glycolipid. -Fatty acids could be saturated (without double bond) or unsaturated (with one or more C=C double bonds). -Oils have a lower melting point (e.g., gingelly oil) and hence remain as oil in winters. So, this statement is correct. -Lipids are all insoluble in polar solvents like water but highly soluble in the non-polar or weakly polar organic solvents, including ether, chloroform, benzene, and acetone. This is the correct statement. -Many lipids have both glycerol and fatty acids. Here the fatty acids are found esterified with glycerol. They can then be monoglycerides, diglycerides and triglycerides. This statement is also correct.

Nucleic acids are polymers of nucleotides. Proteins are polymers of amino acids. Polysaccharides are polymers of monosaccharides and lipids are the esters of fatty acids and alcohol. These are not polymeric.

The transition state structure of the substrate formed during an enzymatic reaction is transient and unstable. Transition state is the state of an activated complex which is highly unstable and readily changes into the product.

Secondary plant metabolites are several chemical compounds produced by the plant cell through metabolic pathways obtained from the primary metabolic pathways. Primary metabolites include small molecules such as sugars, amino acids, tricarboxylic acids, or Krebs cycle intermediates, proteins, nucleic acids and polysaccharides. Many secondary metabolites are toxic or repellant to herbivores and microbes and help to defend plants producing them. Secondary metabolism includes a large number of specialized compounds that do not aid in the growth and development of plants but are required for the plant to survive in its environment.

Antacids-Cimetidine Antihistamines-Seldane Analgesics-Morphine Antimicrobials-Salvarsan

Coenzymes are enzymes loosely attached to an organic molecule. These organic molecules are generally derivatives of vitamins.

A fat molecule consists of two parts: one glycerol backbone and three fatty acid tails. Glycerol is a small organic molecule with three hydroxyl (OH) groups, while a fatty acid consists of a long hydrocarbon chain attached to a carboxyl group.