Question

The graph shows the amount of product formed as substrate concentration increases while the enzyme concentration is held constant.
Which of these explains why the graph levels off at high substrate best concentration?

• A. The reaction has gone to completion
• B. The rate of product formation has slowed due to the addition of an inhibitor
• C. No more substrate is available to be converted into product
• D. The enzyme has been used up and the product cannot be formed without it
• E. All active sites of available enzymes are saturated with the maximum amount of substrate

Answer 1

The correct option is E All active sites of available enzymes are saturated with the maximum amount of substrate

Enzyme concentration affects the rate of reaction. If the substrate concentration is increased, the rate of enzyme reaction also rises. Beyond a certain point, however, the enzyme becomes saturated with substrate molecules. Further increase in reaction velocity occurs only if the enzyme concentration is increased.

So, the correct answer is 'All active sites of available enzymes are saturated with the maximum amount of substrate'