Q16 - ATP and bioenergetics

The correct answer is C) ATP.

ATP is the cell's energy currency. Breaking off its last phosphate releases the energy that drives muscle contraction, active transport and synthesis.

NADH, FADH₂ and NADPH are electron carriers. Their energy has to be turned into ATP first, or used for synthesis in the case of NADPH. Creatine phosphate is a quick backup that rebuilds ATP in muscle.