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

question 100

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.

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