biology cellular respiration

• Respiration


  The process by which the energy trapped in food such as glucose is released and converted into the form of ATP, which the body can then use in various cellular processes
• Respiration


  1. Glycolysis

  2. Citric acid cycle

  3. Electron transport chain
• ATP


  The high-energy molecule that stores the energy released from the breakdown of glucose, which can then be used for various cellular processes
• ATP formation


  1. ADP (low energy)

  2. Phosphorylation (adding a phosphate group)

  3. ATP (high energy)
• To use ATP for cellular tasks

  ATP must be dephosphorylated to release the energy
• Phosphorylation


  The process of adding a phosphate group to a molecule
• Dephosphorylation


  The process of removing a phosphate group from a molecule
• Glycolysis occurs in the cytoplasm, while the majority of ATP is synthesized in the mitochondria during pyruvate breakdown
• Mitochondrial structure


  • Matrix (site of pyruvate breakdown)
  • Inner membrane (site of final stage of respiration)
• Glycolysis

  1. Energy investment phase (ATP used)

  2. Energy payoff phase (ATP produced)
• NAD


  A coenzyme that safely stores hydrogen released during respiration
• Citric acid cycle


  1. Pyruvate broken down to acetyl-CoA

  2. Acetyl-CoA combines with oxaloacetate to form citrate

  3. Citrate broken down, regenerating oxaloacetate, producing ATP and CO2, and more NADH
• Dehydrogenase


  An enzyme that removes hydrogen from substrates, adding it to NAD to form NADH
• Electron transport chain


  1. NADH and FADH2 pass electrons through a series of carrier proteins in the inner mitochondrial membrane

  2. Hydrogen ions are pumped across the membrane, creating a proton gradient

  3. Hydrogen ions flow back through ATP synthase, driving the synthesis of ATP
• Oxygen is the final electron acceptor in the electron transport chain, combining with hydrogen to form water
• ATP is used to provide energy for various cellular processes, such as anabolic reactions, DNA synthesis, and RNA synthesis