Question

Which of the following metabolic conversions involved in glucose synthesis requires the direct expenditure of ATP?

a. 3-Phosphoglycerate --> 1,3-bisphosphoglycerate
b. Glyceraldehyde-3-phosphate + dihydroxyacetone phosphate --> fructose-1,6-bisphosphate
c. Fructose-1,6-bisphosphate --> fructose-6-phosphate
d. 1,3-Bisphosphoglycerate --> glyceraldehyde-3-phosphate

Answer 1

The metabolic conversion that requires the direct expenditure of ATP in glucose synthesis is the conversion of 3-Phosphoglycerate to 1,3-bisphosphoglycerate.

Step-by-step explanation:

The metabolic conversion that requires the direct expenditure of ATP in glucose synthesis is the conversion of 3-Phosphoglycerate to 1,3-bisphosphoglycerate. This conversion involves the phosphorylation of 3-Phosphoglycerate by phosphoglycerate kinase, which uses a phosphate group from ADP and requires the direct expenditure of ATP. This step results in the formation of 1,3-bisphosphoglycerate.

Answer 2

3-Phosphoglycerate --> 1,3-biphosphoglycerate

Step-by-step explanation:

The reaction of 3-Phosphoglycerate --> 1,3-biphosphoglycerate is one of the ten reactions involved in the biosynthesis of glucose, a process also known as gluconeogenesis. This reaction involves the participation of the enzyme Phosphoglycerate kinase, which catalyzes the transfer of one of the phosphate groups from the ATP to the 3-Phosphoglycerate in order to form 1,3-biphosphoglycerate. This then results in an endergonic reaction, as it requires energy for it to occur, and in this case, that energy comes from the ATP molecule, which by losing a phosphate group then becomes an ADP molecule.