Examine the following graph. Which of the following explains why the "line" on the graph does not continue in a linear fashion?
A) All of the added substrate is bound to the enzyme.
B) All of the enzyme active sites are occupied.
C) The amount of enzyme present is greater than needed by the substrate.
D) An inhibitor is present.

Question

Examine the following graph.  Which of the following explains why the "line" on the graph does not continue in a linear fashion?
A) All of the added substrate is bound to the enzyme. 
B) All of the enzyme active sites are occupied. 
C) The amount of enzyme present is greater than needed by the substrate. 
D) An inhibitor is present.

Quizplus · Accepted Answer

The graph shows enzyme activity as a function of substrate concentration. As more substrate is added, enzyme activity increases until a point is reached where all enzyme active sites are occupied. At this point, adding more substrate does not increase enzyme activity, leading to the plateau in the graph. This is known as saturation of the enzyme. Therefore, choice B is the correct answer.

Examine the Following Graph