Glucose Labeled with ¹⁴C in C-3 and C-4 Is Completely

Multiple Choice

Glucose labeled with ¹⁴C in C-3 and C-4 is completely converted to acetyl-CoA via glycolysis and the pyruvate dehydrogenase complex. What percentage of the acetyl-CoA molecules formed will be labeled with ¹⁴C, and in which position of the acetyl moiety will the ¹⁴C label be found?

A) 100% of the acetyl-CoA will be labeled at C-1 (carboxyl) .
B) 100% of the acetyl-CoA will be labeled at C-2.
C) 50% of the acetyl-CoA will be labeled, all at C-2 (methyl) .
D) No label will be found in the acetyl-CoA molecules.
E) Not enough information is given to answer this question.