Intro to Respiration

• Why do our cells need energy?

  • Secretion - exocytosis
  • Maintain constant body temperature
  • Endocytosis
  • Synthesis of organelles
  • Replication of DNA and cell division
  • Activation of chemicals
• What are the word and symbol equations for aerobic respiration?

  Word: Glucose + Oxygen → Carbon Dioxide + Water + 38ATP

  Symbol: C6H12O6 + 6O2 → 6CO2 + 6H2O + 38 ATP
• What is the word equation for anaerobic respiration?

  Glucose  → Lactic Acid
• Stages of respiration (Aerobic)

  • Glycolysis – the splitting of the 6-carbon glucose molecule into two 3-carbon pyruvate molecules
  • The link reaction – pyruvate is converted into carbon dioxide and a 2-carbon molecule called acetyl coenzyme A
  • Krebs cycle – the introduction of acetyl coenzyme A into a cycle of nine reactions that yield some ATP and a large number of electrons
  • Oxidative phosphorylation – electrons are used to synthesise ATP and produce water. Chemiosmosis occurs
• Substrate-level phosphorylation- The formation of ATP from ADP and Pi during glycolysis and the Krebs Cycle
• Oxidative phosphorylation - The formation of ATP, in the presence of oxygen by chemiosmosis