Use the accompanying figure to answer the question(s) below.
-If pyruvate oxidation is blocked, what will happen to the levels of oxaloacetate and citric acid in the citric acid cycle shown in the accompanying figure?
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 accompanying figure to answer the question(s) below. 
-If pyruvate oxidation is blocked, what will happen to the levels of oxaloacetate and citric acid in the citric acid cycle shown in the accompanying figure?
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

If pyruvate oxidation is blocked, then the pyruvate cannot enter the citric acid cycle to be converted into acetyl-CoA, which is then used to produce oxaloacetate and ultimately citric acid. Therefore, the levels of oxaloacetate and citric acid will decrease. However, oxaloacetate is also used to regenerate citric acid in the cycle, so while citric acid will accumulate in the cytoplasm, the levels in the cycle itself will decrease.

Use the Accompanying Figure to Answer the Question(s) Below