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Organisms and Populations — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations1 Mark
Question
For question two statements are given-one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both assertion and reason are true and reason is the correct explanation of assertion.
  2. Both assertion and reason are true but reason is not the correct explanation of assertion.
  3. Assertion is true but reason is false.
  4. Both assertion and reason are false.
Assertion: Ectotherms are able to remain active under cold conditions.
Reason: Ectotherms are able to maintain a constant internal temperature, even when the temperature outside fluctuates.
✓

Answer

  1. Both assertion and reason are false.

Explanation:

Endotherms (warm - blooded animals) can regulate their body temperature by physiological means and are able to maintain a more orless constant internal temperature, even when the temperature outside fluctuates (for example - birds and mammals). They have physiological mechanisms for keeping body temperature constant or within tolerance limits., Ectotherms, (cold-blooded animals) cannot regulate their body temperature and are unable to maintain a constant internal temperature. Their body temperature tends to match with the environmental temperature in which they live, (for example-frogs and snakes).

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