Question

IUBMB has divided enzymes into classes
A. 4
B. 5
C. 6
D. 7

Answer 1

Hint: The International Union of Biochemistry and Molecular Biology (IUBMB) has classified enzymes into several classes. The basis of this classification is according to their action on substrates.

Complete Answer:
Enzymes are the biological catalysts of the living systems. They are capable of promoting biochemical reactions involved in metabolic activities. The substance on which the enzyme acts is called the substrate. The final product formed at the end of the reaction is called the product.

The International Union of Biochemistry and Molecular Biology (IUBMB) has divided enzymes into 6 classes. They are:
1) Oxidoreductases - An oxidoreductase is an enzyme that catalyses the exchange of electrons from one particle, the reductant, likewise called the electron giver, to another, the oxidant, additionally called the electron acceptor. This gathering of chemicals normally uses NADP or $NAD^+$ as cofactors. They catalyse the oxidation and reduction of substrates on which they act.
2) Transferases - These enzymes can transfer atoms or groups from one substrate to the other.
3) Hydrolases - Hydrolases are enzymes that catalyze the cleavage of a covalent bond utilizing water. They are capable of catalysing the hydrolysis of ester, ether, peptide, glycosidic, C-C, C-halide or P-N bonds.
4) Lyases - A lyase is a catalyst that catalyzes the breaking of different compound bonds by processes other than hydrolysis and oxidation, frequently framing another twofold bond or another ring structure.
5) Isomerases - Isomerases are an overall class of chemicals that convert an atom starting with one isomer then onto the next. Isomerases encourage intramolecular modifications in which bonds are broken and framed. They catalyse the interconversion of optical, geometric or positional isomers.
6) Ligases - A ligase is a protein that can catalyse the joining of two compounds. Examples are the enzymes that catalyse linkage of C-O bond, C-S bond, C-N bond, P-O bond, etc.

Hence the correct answer is option C.

Note: The IUBMB Enzyme List is a functional classification system, whereby enzymes are classified based on the overall reaction catalysed by them. Other than six classes, each class is also classified into 4-13 subclasses.