Question

Arrange the steps of catalytic action of an enzyme in right order and select the correct option.
(i) The enzyme releases the products of the reaction and the enzyme is free to bind to another substrate.
(ii) The active site of enzyme is in close proximity of the substrate and breaks the chemical bonds of the substrate.
(iii) The binding of substrate induces the enzyme to alter its shape fitting more tightly around the substrate.
(iv) The substrate binds to the active site of the enzyme fitting into the active site.

• A. iv, iii, ii, i
• B. iii, ii, i, iv
• C. iv, ii, i, iii
• D. ii, i, iv, iii

Answer 1

Answer: (A)

iv, iii, ii, i

Enzymes help reduce the activation energy of the complex molecules in the reaction. Each enzyme has an ‘active site’ which is where the substrate molecules can bind to. This biding helps in the formation of an enzyme-substrate complex. Due to the binding, the active site is in close contact with the substrate. When the bond between the enzyme and the substrate is broken the product is released.

Thus, the correct answer is option A.