• Glycolysis: The first stage of respiration in both aerobic and anaerobic processes, occurring in the cytoplasm, and generating ATP and NADH.
• The Link Reaction: Connects glycolysis to the Krebs Cycle if oxygen is present, producing acetyl coenzyme A and releasing carbon dioxide.
• The Krebs Cycle: Takes place in the mitochondrial matrix, oxidizing pyruvate to form acetate, creating ATP, and producing reduced NAD and FAD through redox reactions.
• Oxidative Phosphorylation: The final stage of aerobic respiration in the inner mitochondrial membrane, generating ATP and water from oxygen through electron transport chain and proton gradient.
• Anaerobic Respiration: Occurs when there is little to no oxygen, leading to the production of lactate in animals or ethanol in plants.

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