alleryStart learning →What happens to the rate of the first reaction of the citric acid cycle when adenosine triphosphate levels rise?
AThe rate stays exactly the same
BThe reaction runs in reverse
CThe rate increases sharply
DThe rate decreases steadily
Answer & Solution
Correct answer: D. The rate decreases steadily
1. The rate of the first reaction is controlled by negative feedback tied to the energy supply.
2. If adenosine triphosphate levels increase, the rate of the reaction decreases.
3. If adenosine triphosphate is in short supply, the rate increases instead.
4. That is the signature of negative feedback, where the product damps its own production.
_Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 7 "Cellular Respiration", section 7.3 Oxidation of Pyruvate and the Citric Acid Cycle_
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