Redox Reactions and ATP in the Cell

Loss of electrons or hydrogen; may release energy.

Gain of electrons or hydrogen; stores energy.

Paired oxidation-reduction process transferring energy.

Molecule transporting electrons (NAD⁺/NADH, FAD/FADH₂).

NAD⁺ accepts electrons → NADH donates them to ETC.

Electron carrier similar to NAD⁺ but yields slightly less ATP.

Main cellular energy currency with high-energy phosphate bonds.

Product after ATP hydrolysis; can be re-phosphorylated.

ATP → ADP + Pi + energy (exergonic).

Addition of phosphate to a molecule to activate or store energy.

Enzyme directly transfers phosphate to ADP to form ATP.

Use of proton gradient across membrane to synthesize ATP via ATP synthase.

Energy from one reaction drives another.

Indicates if reaction is spontaneous or requires energy.