BIO 183: Oxidative Phosphorylation

Oxidative Phosphorylation

the overall process that includes the ETC and chemiosmosis to produce the bulk of cellular ATP

Electron Transport Chain (ETC)

a series of protein complexes embedded in the inner mitochondrial membrane that transfers electrons from NADH and FADH2, releasing energy to pump protons (H+).

Chemiosmosis

the process by which the energy stored in the proton gradient is used by ATP synthase to generate ATP

ATP Synthase

a large, complex protein embedded in the inner mitochondrial membrane that catalyzes the formation of ATP during chemiosmosis

Proton Gradient

the difference in proton (H+) concentration and charge across the inner mitochondrial membrane, which creates an electrochemical gradient that stores potential energy

Final Electron Acceptor

the molecule that accepts the electrons at the very end of the ETC; this is oxygen (O2) in aerobic respiration

Anaerobic Process

a metabolic process, such as fermentation, that occurs without the presence of oxygen

Lactic Acid Fermentation

an anaerobic pathway that converts pyruvate into lactate (lactic acid) and regenerates NAD+; common in muscle cells during strenuous exercise

Alcoholic Fermentation

An anaerobic pathway that converts pyruvate into CO2 and ethanol and regenerates NAD+; used by yeast and some bacteria.

Feedback control/inhibition

A regulatory mechanism where the end product of a metabolic pathway inhibits an enzyme that catalyzes an earlier step in that pathway (e.g., ATP inhibiting Phosphofructokinase).