Question

The phosphorylation of glucose to generate glucose-6-phosphate is catalyzed by the enzyme hexokinase. This enzyme, however, is allosterically inhibited by its own product, glucose-6-phosphate. This is an example of __________.

a. covalent modification
b. irreversible inhibition
c. feedback regulation
d. competitive inhibition

Answer 1

The correct answer is option c. Hexokinase is allosterically inhibited by glucose-6-phosphate, an example of feedback regulation, which conserves resources and balances metabolic supply with demand.

Step-by-step explanation:

The inhibition of hexokinase by its own product, glucose-6-phosphate, is an example of feedback regulation. Feedback regulation is a common mechanism that cells use to regulate metabolic pathways.

In the context of glycolysis, when the concentration of glucose-6-phosphate (G-6-P) increases in the cell, it binds to an allosteric site on hexokinase, which induces a change in the enzyme's structure and decreases its activity. This prevents the unnecessary consumption of glucose when the cell's energy needs are met or when downstream pathways are inhibited.