Use the following figure to answer the questions below.

The citric acid cycle.
-If pyruvate oxidation is blocked, what will happen to the levels of oxaloacetate and citric acid in the citric acid cycle shown in the figure above?
A)There will be no change in the levels of oxaloacetate and citric acid.
B)Oxaloacetate will decrease and citric acid will accumulate.
C)Oxaloacetate will accumulate and citric acid will decrease.
D)Both oxaloacetate and citric acid will decrease.
E)Both oxaloacetate and citric acid will accumulate.

Question

Use the following figure to answer the questions below.
  
The citric acid cycle.
-If pyruvate oxidation is blocked, what will happen to the levels of oxaloacetate and citric acid in the citric acid cycle shown in the figure above?
A)There will be no change in the levels of oxaloacetate and citric acid. 
B)Oxaloacetate will decrease and citric acid will accumulate. 
C)Oxaloacetate will accumulate and citric acid will decrease. 
D)Both oxaloacetate and citric acid will decrease. 
E)Both oxaloacetate and citric acid will accumulate.

Quizplus · Accepted Answer

Pyruvate oxidation provides the acetyl-CoA necessary to start the citric acid cycle. If pyruvate oxidation is blocked, oxaloacetate cannot be converted to citric acid and levels of citric acid will decrease. However, oxaloacetate will accumulate because it cannot be used in the cycle without acetyl-CoA. Therefore, the levels of oxaloacetate will increase while citric acid levels will decrease.

Use the Following Figure to Answer the Questions Below