alleryStart learning →What happens to glucose in a tissue where hexokinase has been inhibited?
AIt is stored as glycogen at once
BIt is converted into amino acids
CIt is oxidized in the mitochondria
DIt diffuses back out of the cell
Answer & Solution
Correct answer: D. It diffuses back out of the cell
1. Hexokinase phosphorylates glucose, and the negative charge of that phosphate stops the sugar leaving.
2. When hexokinase is inhibited, no phosphate is added, so nothing holds the glucose in.
3. Glucose then diffuses out of the cell.
4. It does not become a substrate for the respiration pathways in that tissue.
5. Storage as glycogen requires the phosphorylated form, so that route is closed too.
6. Oxidation in the mitochondria could only follow glycolysis, which never begins here.
_Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 7 "Cellular Respiration", section 7.7 Regulation of Cellular Respiration_
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