Question
  1. State how the constant internal environment is beneficial to organisms.
  2. Explain any two alternatives by which organisms can overcome stressful external conditions.

Answer

  1. Constant internal environment Permits all biochemical reactions and physiological functions to proceed with maximal efficiency and thus, enhance the overall fitness of the species.'
  2. These organisms suspend their metabolic functions during the stressful period and resume their functions at the return of favourable conditions. For example, bear undergoes winter sleep called hibernation and certain animals like snails and fish undergo summer sleep known as aestivation.

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