Aerobic and Anaerobic Respiration

• Cellular respiration is an exothermic reaction which is continuously occurring in living cells.
• The energy transferred from respiration supplies all the energy needed for living processes.
• Respiration in cells 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
• Aerobic respiration equation:

  • glucose + oxygen -----> carbon dioxide + water
• 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.
• 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.