Question

Enzyme concerned with the transfer of electrons are
A. Hydrolase
B. Dehydrogenase
C. Transaminase
D. Protease

Answer 1

Hint:- Enzymes are catalysts which accelerate the rate of chemical reactions. They are mostly proteinaceous in nature. Substrates are the molecules which bind to the active site of enzyme and enzyme in turn catalyses the conversion of substrate molecules to product. The classification of enzymes is done on the basis of reactions they catalyze.

Complete answer:
Step 1: On the basis of reactions they catalyze, enzymes are classified into six classes. They are-
Oxidoreductase- They catalyze the transfer of electrons or hydrogen and oxygen atoms from one substrate to another substrate. Ex- dehydrogenase. Dehydrogenses catalyze the dehydrogenation reactions involving transfer of electrons. Transfer of electrons may result in oxidation or reduction of substrates.
Transferase- They catalyze the transfer of a specific group from one substrate to another. Specific groups are generally phosphate groups, methyl groups, etc. Ex- Transaminase, Kinase.
Hydrolase- They catalyze the hydrolysis of a substrate. Ex- Digestive enzymes.
Isomerases- They catalyze the change of molecular form of substrates. Ex- Phospho hexo isomerase, Fumarase.
Lyase- They catalyze the non-hydrolytic addition or removal of a group from a substrate. Ex- Decarboxylases, Aldolases.
Ligase- They catalyze the formation of bonds resulting in the joining of two molecules. Ex- DNA ligase.

Step 2: Based on the above explanation, it is clear that the correct answer is (B)- Dehydrogenase.

Note:- Enzymes are generally proteinaceous in nature. But, Ribozyme is an exception as it is a non- proteinaceous enzyme. Ribozymes are ribonucleic acid enzymes that are a form of ribosomal RNA and catalyze specific biochemical reactions such as RNA splicing during gene expression.Enzymes only affect reaction rates and not the equilibria.