Page 102 - Biology - XII

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Treating them by dipping in 1% mercuric chloride.

3. Plug mouth of all the fl asks with cotton or one-holed cork. Pass the thermometer through it such that
the bulb of the thermometer is inside the seeds.

Results
1. The temperature rises in some thermometers and in some it does not rise.

Thermometer

Cotton plug
Heat-killed seeds (peas)
Flask

Dry seeds (Peas) Soaked seeds (peas)

Fig. 4.1: Release of heat energy during respiration

Observation Table
Release of heat energy during respiration
Rise in temperature Inference
S. No. Type of seeds in fl ask
1st day 2nd day 3rd day

1. A–Dry seeds _____ °C _____ °C _____ °C

2. B–Soaked seeds _____ °C _____ °C _____ °C

3. C–Heat-killed seeds _____ °C _____ °C _____ °C

Conclusion
1. There is rise in temperature in the fl ask _________ .

2. The temperature rises from _________ °C to _________ °C.
3. There is no rise in temperature in the fl ask _________ .

4. The temperature remains same even after _________ days.
5. There is slight rise in temperature in fl ask _________ .
6. The temperature rises from _________ °C to _________ °C.

Precautions
1. Put the seeds in thermos fl ask carefully.
2. Insert the thermometer carefully.

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