alleryStart learning →How many carbon dioxide molecules are released on each turn of the citric acid cycle?
AFour molecules
BThree molecules
CTwo molecules
DOne molecule
Answer & Solution
Correct answer: C. Two molecules
1. Two carbon atoms come into the cycle from each acetyl group.
2. Two carbon dioxide molecules are released on each turn of the cycle.
3. These do not necessarily contain the most recently added carbon atoms.
4. Over later turns, all six carbon atoms from the original glucose are eventually incorporated into carbon dioxide.
_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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