Which statement about gluconeogenesis in animal cells is TRUE?
A) A rise in the cellular level of fructose-2,6-bisphosphate stimulates the rate of gluconeogenesis.
B) An animal fed a large excess of fat in the diet will convert any fat not needed for energy production into glycogen to be stored for later use.
C) The conversion of fructose 1,6-bisphosphate to fructose 6-phosphate is not catalyzed by phosphofructokinase-1, the enzyme involved in glycolysis.
D) The conversion of glucose 6-phosphate to glucose is catalyzed by hexokinase, the same enzyme involved in glycolysis.
E) The conversion of phosphoenol pyruvate to 2-phosphoglycerate occurs in two steps, including a carboxylation.

Question

Quizplus · Accepted Answer

In glycolysis, fructose-1,6-bisphosphate is converted to glyceraldehyde-3-phosphate and dihydroxyacetone phosphate by the enzyme aldolase. In gluconeogenesis, the reverse reaction occurs, but it is not catalyzed by aldolase. Instead, it is catalyzed by fructose-1,6-bisphosphatase. The conversion of fructose-1,6-bisphosphate to fructose-6-phosphate does not involve phosphofructokinase-1, which is the enzyme involved in glycolysis that catalyzes the reverse reaction (fructose-6-phosphate to fructose-1,6-bisphosphate). A rise in the cellular level of fructose-2,6-bisphosphate stimulates glycolysis and inhibits gluconeogenesis. Animal cells do not convert excess dietary fat into glycogen, but instead store it as fat in adipose tissue. The conversion of glucose-6-phosphate to glucose is catalyzed by glucose-6-phosphatase, not hexokinase. The conversion of phosphoenol pyruvate to 2-phosphoglycerate during gluconeogenesis involves both carboxylation and dephosphorylation, but not in two steps.

Which Statement About Gluconeogenesis in Animal Cells Is TRUE