Glycogenesis: The Synthesis of Glycogen
Glycogenesis is the process by which glucose is converted into glycogen for storage in the liver and muscles. This quiz will test your knowledge of the steps involved in glycogenesis and the enzymes that catalyze these reactions.
Questions
Which enzyme is responsible for the initial phosphorylation of glucose in glycogenesis?
- hexokinase
- glucokinase
- phosphofructokinase
- pyruvate kinase
What is the role of glucose-6-phosphate isomerase in glycogenesis?
- converts glucose-6-phosphate to fructose-6-phosphate
- converts fructose-6-phosphate to glucose-6-phosphate
- converts fructose-1,6-bisphosphate to glucose-1,6-bisphosphate
- converts glucose-1-phosphate to glucose-6-phosphate
Which enzyme catalyzes the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate?
- phosphofructokinase
- fructose-1,6-bisphosphatase
- aldolase
- triose phosphate isomerase
What is the role of aldolase in glycogenesis?
- converts fructose-1,6-bisphosphate to dihydroxyacetone phosphate and glyceraldehyde-3-phosphate
- converts dihydroxyacetone phosphate and glyceraldehyde-3-phosphate to fructose-1,6-bisphosphate
- converts glucose-6-phosphate to fructose-6-phosphate
- converts glucose-1-phosphate to glucose-6-phosphate
Which enzyme catalyzes the isomerization of dihydroxyacetone phosphate to glyceraldehyde-3-phosphate?
- triose phosphate isomerase
- aldolase
- glyceraldehyde-3-phosphate dehydrogenase
- phosphoglycerate kinase
What is the role of glyceraldehyde-3-phosphate dehydrogenase in glycogenesis?
- converts glyceraldehyde-3-phosphate to 1,3-bisphosphoglycerate
- converts 1,3-bisphosphoglycerate to glyceraldehyde-3-phosphate
- converts dihydroxyacetone phosphate to glyceraldehyde-3-phosphate
- converts fructose-1,6-bisphosphate to dihydroxyacetone phosphate and glyceraldehyde-3-phosphate
Which enzyme catalyzes the phosphorylation of 1,3-bisphosphoglycerate to 3-phosphoglycerate?
- phosphoglycerate kinase
- glyceraldehyde-3-phosphate dehydrogenase
- triose phosphate isomerase
- aldolase
What is the role of phosphoglycerate mutase in glycogenesis?
- converts 3-phosphoglycerate to 2-phosphoglycerate
- converts 2-phosphoglycerate to 3-phosphoglycerate
- converts phosphoenolpyruvate to pyruvate
- converts pyruvate to phosphoenolpyruvate
Which enzyme catalyzes the dehydration of 2-phosphoglycerate to phosphoenolpyruvate?
- enolase
- phosphoglycerate kinase
- phosphoglycerate mutase
- glyceraldehyde-3-phosphate dehydrogenase
What is the role of pyruvate kinase in glycogenesis?
- converts phosphoenolpyruvate to pyruvate
- converts pyruvate to phosphoenolpyruvate
- converts glucose-6-phosphate to fructose-6-phosphate
- converts fructose-1,6-bisphosphate to dihydroxyacetone phosphate and glyceraldehyde-3-phosphate
Which enzyme catalyzes the transfer of the glycosyl unit from UDP-glucose to glycogen?
- glycogen synthase
- glycogen phosphorylase
- glycogen branching enzyme
- glycogen debranching enzyme
What is the role of glycogen branching enzyme in glycogenesis?
- creates branch points in the glycogen molecule
- removes branch points from the glycogen molecule
- transfers the glycosyl unit from UDP-glucose to glycogen
- converts glucose-6-phosphate to fructose-6-phosphate
Which enzyme catalyzes the removal of branch points from the glycogen molecule?
- glycogen debranching enzyme
- glycogen branching enzyme
- glycogen synthase
- glycogen phosphorylase
What is the role of glycogen phosphorylase in glycogenesis?
- catalyzes the breakdown of glycogen to glucose-1-phosphate
- catalyzes the synthesis of glycogen from glucose-1-phosphate
- creates branch points in the glycogen molecule
- removes branch points from the glycogen molecule
Which hormone stimulates the breakdown of glycogen to glucose-1-phosphate?
- glucagon
- insulin
- epinephrine
- growth hormone