Respiration

• Respiration


  An enzyme-controlled process in which high-energy content food (eg glucose) is broken down (catabolism) to release energy. This process occurs in cells.
• Types of respiration


  • Aerobic respiration
  • Anaerobic respiration
• Aerobic respiration


  • Breakdown of food using oxygen
  • Occurs in the mitochondria of all air-breathing organisms
  • Produces carbon dioxide, water and ATP
• Aerobic respiration equation

  C6H12O6 + 6O2 → 6CO2 + 6H2O + 38ATP
• Anaerobic respiration


  Breakdown of food without using oxygen
• Anaerobic respiration - lactic acid production


  C6H12O6 → 2C3H6O3 + 2ATP
• Adenosine Tri-phosphate (ATP)


  An energy-rich chemical produced during respiration
• ATP production


  ADP + phosphate group + energy → ATP
• Not all the energy released during respiration is used to make ATP, some is released as heat
• The energy produced during aerobic respiration is used in:

  -working muscles

  -transporting chemicals

  -sending messages along the nerves

  -growth (building cells)

  -keeping the body temperature constant
• Anaerobic respiration


  The breakdown of food without using oxygen
• Fermentation


  • Alcoholic drinks made by yeast fermenting sugar in fruit juice
  • Beer made by yeast fermenting barley
  • Cider made by yeast fermenting apple juice
• During heavy exercise


  Cells respire anaerobically to produce energy, breaking down glucose to lactic acid without using oxygen
• After heavy exercise


  Lactic acid is broken down in the liver using extra oxygen, causing the body to keep panting and breathing faster (oxygen debt)
• Recovery time


  The time it takes for breathing rate to return to normal after all the lactic acid is broken down
• Biotechnology


  • Production of milk and yogurt
• Bacteria produce methane, silage and vinegar