AP BIOLOGY

Detailed explanation-1: -A Lock and Key analogy may be used to describe the fundamental action of a single substrate enzyme . In this case, the enzyme is the lock, and the substrate is the key. Only the correct size key, which is the substrate, enters the keyhole, which is the active site of the lock, which is the enzyme.

Detailed explanation-2: -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-3: -The lock-and-key model portrays an enzyme as conformationally rigid and able to bond only to substrates that exactly fit the active site. The induced fit model portrays the enzyme structure as more flexible and is complementary to the substrate only after the substrate is bound.

Detailed explanation-4: -Enzymes Sites Are Keyholes Each enzyme has receptor sites that allow specific substrates to enter and create a chemical reaction product. The enzyme sites work like the keyhole in a lock. Like the lock on a door, only certain keys will fit in the keyholes, and perhaps only one key will open the lock.