Germinating seeds. Image credit

Germinating seeds. Image credit

ZIMSEC O Level Combined Science Notes: Experiment: Is energy released by germinating seeds?

Aim:  Determine whether energy is released when seeds are germinating.

Hypothesis: Seeds are structures produced by plants (living organisms). They respire when they are germinating.

Materials: tow insulated containers/vacuum flasks, two supporting stands, two thermometers, large amount of soaked seeds, cotton wool, mild disinfectant.


Experiment set up. Image credit

Experiment set up. Image credit

  1. Soak the seeds overnight to soften their testas.
  2. Boil half of the soaked seeds to kill them. Allow them to cool and wash them in a mild disinfectant ( to kill any other living organisms that might be in the seeds).
  3. Wash the unboiled seeds in a mild disinfectant as well.
  4. Place the seeds insulated containers and insert thermometers.
  5. Plug them with cotton wool.
  6. Make sure you place the same amount of seeds in each of the containers.
  7. Record the temperature in each container.
  8. Record the temperature at the same time each day.


  • The temperature of the boiled seeds remains unchanged.
  • The temperature of the unboiled seeds increases gradually and levels off as the seeds begin germinating.


  • Energy is released during the germination process.
  • Seeds respire and release energy during the germination process.
  • Heat is produced during the respiration process.

NB The boiled seeds are the control in this instance.

To access more topics go to the Combined Science Notes page.