The following diagram shows the "lock & key" model for enzymes and their substrates. The model uses sucrose as an example, but the model works for any enzyme and substrate.

Question

In 2-4 sentences, respond to the following points:

Explain how the lock and key model describes the interaction between an enzyme and its substrates.
Explain why the lock and key model is important for regulating or controlling the various enzyme processes in cells.
(4 points)

Answer 1

The lock and key model describes the interaction between an enzyme and its substrates by illustrating how the enzyme (the lock) has a specific active site shape that perfectly fits the substrate (the key), allowing for a precise binding. This specificity is crucial because it ensures that enzymes catalyze only particular reactions, thereby regulating metabolic pathways and preventing unwanted or side reactions in the cell. By maintaining such specificity, the lock and key model helps control the various enzymatic processes essential for maintaining cellular function and homeostasis.