Which molecule serves as the primary energy currency in aerobic respiration?

Which molecule serves as the primary energy currency in aerobic respiration?

• A. NADH.
• B. ATP.
• C. GTP.
• D. ADP.

Answer: (B)

ATP is the molecule cells rely on as the immediate energy currency. In aerobic respiration, energy from food is captured first in high-energy carriers like NADH and FADH2, and some ATP is produced directly through substrate-level phosphorylation. But the primary way this energy is used is by converting ADP and inorganic phosphate into ATP, which can be quickly hydrolyzed to release the exact amount of energy needed for a wide range of cellular processes. ATP produced in mitochondria via oxidative phosphorylation is especially important because it serves as the universal energy source for enzymes, motor proteins, and transport mechanisms. NADH and FADH2 mainly act as carriers that feed electrons into the chain to drive ATP production, while GTP is used in a few specific reactions, and ADP is simply the substrate that becomes ATP.

ATP is the molecule cells rely on as the immediate energy currency. In aerobic respiration, energy from food is captured first in high-energy carriers like NADH and FADH2, and some ATP is produced directly through substrate-level phosphorylation. But the primary way this energy is used is by converting ADP and inorganic phosphate into ATP, which can be quickly hydrolyzed to release the exact amount of energy needed for a wide range of cellular processes. ATP produced in mitochondria via oxidative phosphorylation is especially important because it serves as the universal energy source for enzymes, motor proteins, and transport mechanisms. NADH and FADH2 mainly act as carriers that feed electrons into the chain to drive ATP production, while GTP is used in a few specific reactions, and ADP is simply the substrate that becomes ATP.