Question

Gluconeogenesis is favored when citrate levels are __________, when AMP levels are __________, and when ATP levels are __________.

Select one:

a. low; low; high

b. high; low; high

c. low; high; low

d. high; high; low

Answer 1

Solution:-

Gluconeogenesis is the metabolic process which create glucose from other molecules and also allows the body to store the needed energy for the brain in the form of glucose. Gluconeogenesis is like glycolysis but the process occurs in reverse. In gluconeogenesis the conversion of pyruvate to PEP is regulated by acetyl CoA. The conversion of fructose-1,6bP to fructose-6-P with the use of enzyme fructose-1,6-phosphatase is negatively regulated and inhibited by AMP and fructose-2,6-bP. The conversion of glucose-6-P to glucose with the use of glucose-6-phosphatase is controlled by substrate level regulation. Increase in glucose-6-P and glucose-6-phosphatase means more glucose which means glycolysis unable to produce.

The conversion of fructose-6-P and fructose-1,6-bP is highly controlled. AMP stimulates phosphofructokinase whereas ATP and citrate inhibits it. On the other hand fructose-1,6-bP is inhibited by AMP and activated by citrate. High level of AMP indicates that the energy charge is low and signals the need for ATP production. Conversely, high level of ATP and citrate indicate that the energy is high which shows glycolysis is going to slowdown and gluconeogenesis is activated.

So, the answer is option (b) high, low, high.