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In an experiment, disinfected soaked bean seeds were put in a vacuum flask which was then fitted with a thermometer as shown in the diagram below.\

The temperature readings were taken every morning for three consecutive days.
(a) Which process was being investigated?
(b) (i) What were the expected results?
(ii) Account for the answer in (b) (i) above
(c) Why were the seeds disinfected?
(d) Why was a vacuum flask used in the set up?
(e) How would a control for this experiment be set?

Answer Text:
a)- Respiration/ aerobic respiration
b)i)- An increase in temperature on the thermometer reading.
ii)- Stored starch in germinating seeds are broken down then oxidized to get energy. Some of the energy is released as heat which raises the temperature.
c)- To kill bacteria/fungi that would cause decay/ decomposition or respiration of the micro-organisms which could raise heat.
d)- To conserve heat/prevent heat loss to surrounding.
e)- Use a similar set up with dead disinfected boiled seeds or use dry bean seeds.