Aerobic Respiration in detail

• Aerobic respiration requires oxygen
• Aerobic respiration consists of three main stages: glycolysis, the Krebs cycle, and oxidative phosphorylation
• Glycolysis:

  • Occurs in the cytoplasm of the cell
  • Does not require oxygen
  • Splits glucose into two pyruvate molecules
  • Produces two molecules of ATP and NADP molecules
• Transition Reaction:

  • Converts each pyruvate molecule into Acetyl-CoA before entering the Krebs cycle
  • Occurs in the mitochondrial matrix
  • Links glycolysis with the Krebs cycle
• Krebs Cycle:

  • Requires oxygen
  • Occurs in the mitochondrial matrix
  • Coenzyme A releases the acetyl group to combine with compounds in the cycle
  • Generates 2 CO2, 2 ATP, 6 NADH, and 2 FADH2 per glucose molecule
• In cellular respiration's final stage, the electron transport chain (ETC) and chemiosmosis happen in the mitochondrial inner membrane. NADH and FADH2 donate electrons, becoming NAD+ and FAD. Cytochromes pass electrons to generate ATP from ADP. Oxygen is the final electron acceptor, forming water in chemiosmosis.
• Chemiosmosis is how electron gradient transport creates ATP. Hydrogen ions move from the high concentration in the mitochondrial matrix to the inter-membrane space. Then, through ATP synthase, they flow back, generating ATP using the released energy.