Question

At the end of the CAC, most of the energy remaining from the original glucose is carried away by

a) ATP molecules
b) Carbon dioxide
c) Oxygen molecules
d) NADH molecules

Answer 1

NADH molecules carry most of the energy remaining from the original glucose after the Citric Acid Cycle, with these high-energy electrons being essential for subsequent ATP production.

Step-by-step explanation:

At the end of the Citric Acid Cycle (CAC), most of the energy remaining from the original glucose molecule is primarily carried away by NADH molecules. During the CAC, each turn produces three NADH molecules and one FADH₂ molecule, which will be used in the electron transport chain to produce ATP. Carbon dioxide is also produced, representing the oxidized carbon atoms from the glucose.

However, the bulk of the energy harnessed from glucose is held in the high-energy electrons of NADH and FADH₂ that are pivotal for ATP production in the later stages of cellular respiration.