Chapter 9: Biomolecules

1. In the first step, the substrate binds to the active site of the enzyme which fits into the active site

2. The binding of the substrate will help the enzyme to alter its shape and will fit more tightly

3. The active site of the enzyme breaks the chemical bond of the substrate thus forming a new enzyme product

4. The product will be released by the enzymes in the reaction and the free enzyme is ready to bind the substrate of another molecule and once again run through the catalytic cycle.

There are different classes of enzymes. They are Oxidoreductase, Transferase, Hydrolase, Lysates, Isomerase, ligases.

a) Oxidoreductase:

These are the enzymes which help in simultaneous oxidation and reduction of two substrates.

S reduced + S’reduced → S oxidized + S’ oxidized

b) Hydrolases:

These enzymes facilitate the hydrolysis of a molecule.

Sucrose → Glucose + Fructose

DNA is made up of two polypeptide chains, arranged in a double helix. The backbone is of sugar-phosphate while the nitrogenous bases are present on the inner side. These nitrogenous bases pairs to each other by H bonds. This H bond confers for the stability of helix.

Nucleotides are the monomers of nucleic acid and are formed of nucleoside and phosphate group. Whereas nucleosides are the constituent of nucleotides. Adenosine, guanosine, thymidine, uridine and cytidine are nucleosides. Adenylic acid, thymidylic acid, guanylic acid, uridylic acid and cacodylic acid are nucleotides.

Lipids are classified into three categories:

Simple lipids, compound lipids and derivatives.

Simple lipids are the esters of fatty acids eg: Triglycerol, fats and wax

Compound lipids are with an additional group other than fats and alcohols. An example is phospholipids, glycolipids

When lipids consist of hydrocarbon ring and the long chain of hydrocarbons they are called derivatives

Examples of Steroids, Cholesterol.

Biomolecules can be defined as molecules present in different organisms, which are responsible for a whole host of biological processes. Different processes, such as cell division and development, are run by biomolecules. Some types of biomolecules are as follows.

1. Metabolites
2. Hormones
3. Neurotransmitters
4. Vitamins
5. Lipids and Fatty acids