Pyruvate Oxidation, Citric Acid Cycle, & Oxidative Phosphorylation

Lecture 19

Pyruvate Oxidation

occurs in the mitochondria when O₂ is present; pyruvate converts into acetyl-CoA

Citric Acid Cycle (Krebs Cycle)

Acetyl-CoA + oxaloacetate → citrate

Citrate donates e^- to NADH → NADH+

Citrate decomposes; 2 CO₂ molecules released, 4-carbon molecule is rearranged to create oxaloacetate

Net products of 1 ATP, 3 NADH, & 1 FADH₂

Electron Transport Chain

occurs in the mitochondria; accepts e^- from NADH and FADH₂, pumping H⁺ ions which make H₂O

Proton Gradient

a concentration of protons formed when the H⁺ ions are pumped out, storing potential energy to synthesize ATP

Net products at the end of the Citric Acid Cycle

2 ATP, 6 NADH, 2 FADH₂

Oxidative Phosphorylation

process in which energy from NADH and FADH₂ are used to synthesize ATP

Chemiomosis

the H⁺ gradient drive ATP synthase which produces ATP

Amount of glucose’s energy converted into ATP

34% efficiency, ~32 ATP per glucose