083 ESTIMATION OF RATE OF RESPIRATION (SEEDS)

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083 ESTIMATION OF RATE OF RESPIRATION (SEEDS)
To understand respiration by germinating seeds
MATERIALS REQUIRED
Injection bottle with rubber lid. Empty ball pen
refill. Germinating seeds. Cotton. Potassium
hydroxide pellets (KOH)
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Roll 2-3 KOH pellets in cotton and place at the
bottom of the injection bottle. Place few
germinating seeds into the bottle and plug the
mouth of the bottle with the rubber lid. Make a
small hole in the lid. Insert the empty
ballpoint pen refill through this hole and
introduce little coloured water into this tube.
Mark the water level with ink or tie a
thread. Record change in the level of water at
regular intervals of time. As the seeds respire
carbon dioxide is absorbed by KOH and as air
enters through the refill the coloured water
moves towards the bottle.