Respiration

• What is the aim for this practical?

  To measure oxygen consumption during respiration.
• The steps:

  • Place living organisms (e.g., germinating seeds) in a respirometer.
  • Use a soda lime to absorb CO₂.
  • Measure movement of a drop of liquid in a capillary tube.
  • Repeat for different conditions (e.g., temperature).
• What is the independent variable?

  Temperature or organism type.
• What is the dependent variable?

  Oxygen used (movement of liquid).
• What is the control variable?

  Same volume of soda lime.