Question
Explain by taking three different examples, how certain organisms pull through the adverse conditions, when unable to migrate under stressful period.
✓
Answer
Organisms overcome the stressful conditions that are of short duration in the following ways:
- The animals migrate, i.e. they move away from the stressful habitat to a more hospitable area and return to their habitat when the stressful period is over, e.g. Birds from Siberia and other cold countries migrate to Bharatpur Sanctuary in Rajasthan.
- Animals which cannot migrate, suspend/ reduce their metabolic activity and avoid stress by escaping in time.
- They show hiberation, i.e., escaping in time during winters, e.g. bears and frogs.
- They may go into aestivation, i.e. escaping in time to avoid summer-related problems, e.g. snails and fish.
- Zooplanktons enter diapause, a state of suspended development.
- In bacteria, fungi and lower groups of plants, various types of thick-walled spores are formed; they germinate under suitable conditions.
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