biology- respiration

• The equation for aerobic respiration is glucose + oxygen → carbon dioxide + water.
• Anaerobic respiration occurs when there isn't enough oxygen to complete the process, resulting in less energy being produced.
• In anaerobic respiration, pyruvate molecules are converted into lactic acid or ethanol instead of entering the citric acid cycle.
• Anaerobic respiration occurs when there isn't enough oxygen to complete the process, resulting in less ATP being produced compared to aerobic respiration.
• Aerobic respiration


  Process of releasing energy from glucose, using oxygen
• Respiration


  1. Glucose

  2. Oxygen

  3. Carbon dioxide

  4. Water

  5. Energy
• Respiratory system


  Function is to obtain sufficient oxygen for respiration and remove the waste gas carbon dioxide
• Investigating respiration in germinating peas

  1. Peas respire, releasing heat

  2. Temperature goes up

  3. Peas covered in boiling water, no respiration

  4. Temperature still increases slightly
• Inspiration


  1. Intercostal muscles contract

  2. Diaphragm contracts

  3. Chest cavity increases in volume

  4. Pressure decreases

  5. Air is sucked in
• Expiration


  1. Intercostal muscles relax

  2. Diaphragm relaxes

  3. Chest cavity decreases in volume

  4. Pressure increases

  5. Air is forced out
• Gas exchange


  • Oxygen diffuses into blood capillaries
  • Carbon dioxide diffuses out of blood capillaries
• Anaerobic respiration


  Shorter series of enzyme-controlled reactions that partly breaks down glucose, releasing only some energy, can occur without oxygen
• Anaerobic respiration


  1. Glucose

  2. Lactic acid

  3. Energy
• Oxygen debt


  Amount of oxygen needed to remove the toxic lactic acid produced during anaerobic respiration, must be paid back when oxygen is available