Question

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

• A. (D), (C), (B), (A)
• B. (C), (B), (A), (D)
• C. (D), (B), (A), (C)
• D. (B), (A), (D), (C)
• E. (C), (D), (A), (B)

Answer 1

Answer: (A)

(D), (C), (B), (A)

It is now well accepted that enzyme molecule binds to a substrate molecule to form an enzyme substrate complex. The three dimensional structure of enzyme molecule is altered by formation of enzyme substrate complex. This alteration promotes cleavage of bonds in substrates and its conversion to products is facilitated by interaction between enzyme molecule and the substrate molecule. Ultimately the product molecule is released from the active site of enzyme and enzyme regains its original three dimensional structure.