GENERAL KNOWLEDGE

Detailed explanation-1: -The lock-and-key theory of enzyme action proposes that the enzyme’s active site and the shape of the substrate molecule are complementary to one another. This allows the substrate to fit into the enzyme, like how a key would fit into a lock. If the substrate doesn’t fit, then the enzyme will not act on it.

Detailed explanation-2: -A theory to explain the mechanism of enzymatic reactions, in which it is proposed that the enzyme and substrate(s) bind temporarily to form an enzyme–substrate complex. The binding site on the enzyme is known as the ‘active site’ and is structurally complementary to the substrate(s).

Detailed explanation-3: -The theory was postulated by Emil Fisher in 1898. According to the hypothesis, like a lock can be open by its key only, a substance possessing specific composition only can combine with the specific active site found in the specific enzyme’s surface.

Detailed explanation-4: -Explanation: The lock and key model states that the active site of an enzyme precisely fits a specific substrate. The induced fit model states that the active site of an enzyme will undergo a conformational change when binding a substrate, to improve the fit.