Gluconeogenesis

Von Gierke’s disease results from a defect in glucose-6-phosphatase. What is the major consequence of this condition?

• Ketosis

• Hyperglycemia (raised blood sugar)

• Hypoglycemia (low blood sugar between meals)

• Diabetes

• Lactose intolerance

Which of the following enzymes does NOT participate in gluconeogenesis?

• Fructose-1,6-bisphosphatse

• Pyruvate kinase

• PEP carboxykinase

• Pyruvate carboxylase

• Phosphoglycerate kinase

The targets for allosteric regulation by fructose-2,6-bisphosphate are:

• Phosphofructokinase-1 and fructose-1,6-bisphosphatase

• Pyruvate kinase and pyruvate carboxylase

• Pyruvate kinase and phosphoenolpyruvate carboxykinase

• Phosphofructokinase-1 and phosphofructokinase-2

• Hexokinase and glucose-6-phosphatase

How many nucleoside triphosphates (ATP + GTP) are required to convert two pyruvate to glucose?

• 0

• 1

• 2

• 3

• 6

The reactions of glycolysis that are replaced in gluconeogenesis are those that:

• Are substrate level phosphorylations

• Are oxidation/reduction reactions

• Operate close to equilibrium

• Have large positive Gibbs free energy changes (in the direction of glycolysis).

• Have large negative Gibbs free energy changes (in the direction of glycolysis).

Tags

NGSS.HS-PS1-4

Glucagon stimulates gluconeogenesis by:

• Stimulating the phosphorylation of fructose-1,6-bisphosphatase

• Allosterically activating fructose-1,6-bisphosphatase

• Stimulating the phosphorylation of PFK-2 so that fructose-2,6-bisphosphate is converted to fructose-6-phosphate

• Activating PFK-2 so that fructose-2,6-bisphosphate is synthesized from fructose-6-phosphate

• Inhibiting PFK-1 to slow down glycolysis

Gluconeogensis in __________ provides a source of ___________ for transport in the bloodstream and use by ___________.

• Muscle; glucose-6-phosphate; liver

• Muscle; glucose; liver

• Liver; ATP; brain

• Liver; glucose; brain and muscle

• Liver; glucose-6-phosphate; brain

The major site of glucose synthesis is:

• Muscle

• Liver

• Brain

• Muscle and liver

• Muscle and brain

Gluconeogenesis is the synthesis of:

• Glucose from non-carbohydrate precursors

• Glycogen from glucose

• Pyruvate from glucose

• Fatty acids from glucose

• Glucose from fatty acids (At best, fatty acids can be used to form Acetyl-CoA to go into the TCA cycle, but sadly cannot ever form glucose)

Which of the following exerts reciprocal regulation on glycolysis and gluconeogenesis by acting as an allosteric activator of PFK-1 and an allosteric inhibitor of fructose-1,6-bisphosphatase

• Fructose-6-phosphate

• Fructose-2,6-bisphosphate (formed by phosphorylation of F6P by PFK2, PFK2 regulated by a post-translation modification – phosphorylation)

• Glucagon

• Fructose-1,6-bisphosphate

• Insulin