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Organisms and Populations — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations1 Mark
MCQ
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.
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.
  • A
    Both assertion and reason are true and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true but reason is not the correct explanation of assertion.
  • C
    Assertion is true but reason is false.
  • ✓
    Both assertion and reason are false.
✓

Answer

Correct option: D.
Both assertion and reason are false.
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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