Respiration

• Respiration is the transfer of energy from glucose and occurs in every cell.

  Endothermic reactions take in energy that has been transferred from glucose in respiration from the surroundings.

  Exothermic reactions transfer energy to the surroundings, e.g. respiration, breaking down excess protein into urea.

  Metabolism is the sum of all the chemical reactions that occur in the body and can be affected by one’s lifestyle choices, the amount of exercise one does and their diet.
• The energy produced by respiration:

  • allows muscle contraction
  • keeps the body warm
  • builds larger molecules from smaller ones - these are all endothermic
  • moves minerals into cells via active transport into the roots and then into the rest of the plant.
• Aerobic respiration is when glucose is broken down with the presence of glucose and this takes place in the mitochondria.

  Glucose + oxygen → carbon dioxide + water (+38 ATP molecules)

  ATP is the energy currency molecule of all living organisms. 

  C6H12O6 + 602 → 6CO2 + 6H2O
• Anaerobic respiration occurs more rarely and occurs during vigorous activity such as sprinting or bodybuilding. This is because here your muscles are working extremely hard, and their demand for oxygen is higher than the supply they receive. 

  The glucose isn’t oxidised and doesn’t break down completely.

  In muscle cells: Glucose → lactic acid (+ 2 ATP molecules)

  In plants and fungi: glucose → ethanol + carbon dioxide (+ 2 ATP molecules)
• Both reactions release energy and both transfer their energy from glucose. Aerobic uses oxygen but anaerobic doesn’t, and they produce different products. Aerobic respiration is the complete breakdown of glucose while anaerobic is incomplete.