B4

• Photosynthesis rate

  • Increased by increasing temperature
  • Increased by increasing light intensity
  • Increased by increasing CO2 concentration
• Uses of glucose

  • Respiration
  • Making starch/fat to store energy
  • Making amino acids for proteins
• Photosynthesis practical

  1. Cut pondweed stem

  2. Put in inverted measuring cylinder filled with water

  3. Add sodium hydrogen carbonate to provide CO2

  4. Measure distance from light source

  5. Acclimatise

  6. Measure volume of oxygen

  7. Repeat at different distances from light source
• Aerobic respiration

  Glucose + oxygen> water + carbon dioxide
• Anaerobic respiration


  Glucose> lactic acid
• Anaerobic respiration occurs during intense exercise which causes oxygen debt
• Anaerobic respiration in plants

  Glucose> ethanol + carbon dioxide (also known as fermentation)
• During exercise

  Heart and breathing rate increase to increased blood flow and supply more oxygen and glucose to enable muscles to contract
• Respiration

  Provides energy for chemical reactions, warmth and movement
• Metabolism


  The chemical reactions in a cell organism, for example fatty acids> lipids (fats) and respiration