Question

Cellular respiration completely breaks down a glucose molecule through glycolysis and the citric acid cycle. However, these two processes yield only a few ATPs. The majority of the energy the cell derives from glucose is _____.

Answer 1

temporarily stored in NADH and FADH2

Step-by-step explanation:

Redox reactions of glycolysis and Kreb's cycle form NADH and FADH2. These reducing powers are oxidized during oxidative phosphorylation by giving their electrons to the terminal electron acceptor, the molecular oxygen. Transfer of electrons from NADH and FADH2 to molecule oxygen occurs via electron transport chain.

This step-wise electron transport produces electrochemical gradient across the inner mitochondrial membrane which in turn drives the synthesis of a large number of ATPs. Oxidation of one NADH and FADH2 obtains around 3 and 2 ATP molecules respectively. Total 10 NADH and 2 FADH2 are formed by one glucose molecule during glycolysis and Kreb's cycle.