.1 Aerobic and anaerobic respiration

• The energy transferred supplies all the energy needed for living processes
• Respiration in cells can take place aerobically (using oxygen) or anaerobically (without oxygen), to transfer energy.
• differing products and the relative amounts of energy transferred. Organisms need energy for:

  chemical reactions to build larger molecules

  movement

  keeping warm.
• Aerobic respiration is represented by the equation:

  glucose + oxygen → carbon dioxide + water
• Anaerobic respiration in muscles is represented by the equation:

  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 is represented by the equation:

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