If glucose labeled with ¹⁴C at C-2 were metabolized in the liver, the first radioactive pyruvate formed would be labeled in:

Question

Quizplus · Accepted Answer

Glucose labeled at C-2 means that the second carbon of glucose is labeled. During glycolysis, glucose is converted to pyruvate. Pyruvate is a 3-carbon compound that contains a carbonyl group (C=O) and a carboxyl group (COO-). The second carbon of glucose becomes the carbonyl carbon of pyruvate. Therefore, the first radioactive pyruvate formed would be labeled at its carbonyl carbon, which is the second carbon of glucose.

If Glucose Labeled with 14C at C-2 Were Metabolized in the Liver

If Glucose Labeled with ¹⁴C at C-2 Were Metabolized in the Liver