alleryStart learning →What inhibits the forward direction of the reaction that turns pyruvic acid into lactic acid?
AAcidic conditions
BAlkaline conditions
CVery cold conditions
DVery dry conditions
Answer & Solution
Correct answer: A. Acidic conditions
1. The lactate dehydrogenase reaction can proceed in either direction.
2. The direction from pyruvic acid to lactic acid is inhibited by acidic conditions.
3. Lactic acid is itself an acid, so its build-up slows the very reaction that makes it.
4. That is a self-limiting arrangement rather than an outside control.
5. Alkaline conditions are not named as an inhibitor anywhere in this reaction.
6. Temperature and dryness play no stated part in the direction this reaction takes.
_Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 7 "Cellular Respiration", section 7.5 Metabolism without Oxygen_
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