Aerobic and anaerobic respiration

• Cellular respiration is an exothermic reaction which is continuously occurring in living cells
• The energy transferred supplies all the energy needed for living processes
• Respiration in can take place aerobically (using oxygen) or anaerobically (without oxygen), to transfer energy
• Organisms need energy for:

  • chemical reactions to build larger molecules
  • Movement
  • keeping warm
• Equation for aerobic respiration:

  glucose + oxygen -> carbon dioxide + water
• Equation of anaerobic respiration in muscles:

  glucose -> lactic acid
• As the oxidation of glucose is incomplete in anaerobic respiration, much less energy is transferred than in aerobic respiration
• Equation for anaerobic respiration in plant and yeast cells:

  glucose -> ethanol + carbon dioxide
• Anaerobic respiration in yeast cells is called fermentation and has economic importance in the manufacture of bread and alcoholic drinks.