What are the main steps in aerobic respiration? Where does it take place?

aerobic respiration takes place in the cytoplasm and mitochondria of eukaryotic cells

glycolysis

• occurs in the cytosol of the cell

• breaks one glucose (6-carbon) into two pyruvate molecules (3-carbon each)

• net yield of 2 ATP and 2 NADH per glucose

pyruvate oxidation (link reaction)

• takes place in the mitochondrial matrix after pyruvate is transported from the cytosol

• pyruvate is decarboxylated and combined with coenzyme A to form acetyl-CoA, releasing CO₂

• generates 1 NADH per pyruvate (2 NADH per original glucose)

citric acid cycle (Krebs cycle)

• occurs in the mitochondrial matrix

• acetyl-CoA (2-carbon) enters the cycle and is oxidized to 2 CO₂ molecules

• produces per acetyl-CoA: 3 NADH, 1 FADH₂, 1 GTP (convertible to ATP)

oxidative phosphorylation

• located on the inner mitochondrial membrane (cristae)

• electron transport chain transfers electrons from NADH and FADH₂ to molecular oxygen, forming water

• proton gradient established across the inner membrane drives ATP synthase to produce ~34 ATP per glucose