Under which conditions is gluconeogenesis active? Multiple answers: You can sele
ID: 165371 • Letter: U
Question
Under which conditions is gluconeogenesis active?
Multiple answers: You can select more than one option
A. during oxidation of glucose.
B. when glucose is present in short supply.
C. gluconeogenesis is super active when cells starve (e.g. deprived of a suitable carbon source) they begin to reverse their anabolic pathways degrading amino acids fatty acids nucleic acids and other macromolecules supplying the breakdown products (carbon skeletons that are intermediates of the TCA and glycolysis pathway) to resynthesize glucose
D. gluconeogenesis is an alternative pathway that takes care of excessive amounts of glucose.
Explanation / Answer
Answesr: (B), (C)
Gluconeogenesis is activated when there is short supply of glucose or the cells starve.
When blood glucose is abundant, as it is after a meal, glucagon concentration in the blood falls and insulin levels in the blood rise. Now, gluconeogenesis is not needed and the phosphoryl group is removed from the bifunctional enzyme. This covalent modication activates PFK2 and inhibits FBPase2. The resulting rise in the level of F-2,6-BP accelerates glycolysis.
Gluconeogenesis and glycolysis are coordinated so that, within a cell, one pathway is relatively inactive while the other one is highly active.
In case of excess glucose in the body, insulin signaling activates glycogen synthesis and inhibits/suppresses gluconeogenesis.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.