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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: Kangaroo rat can live without drinking water.
Reason: This is an adaptation to water scarcity in arid conditions.
✓

Answer

  1. Both assertion and reason are true and reason is the correct explanation of assertion.

Explanation:

Two types of adaptations are prominent in animals living in arid regions,viz. loweringofwaterloss as much as possible and adapting to arid conditions. The kangaroo rat conserves water by excreting solid urine, and can live from birth to death without even drinking water. The camels show unique adjustments to desert conditions, being very economical in water use, tolerant to wide fluctuations in body temperature and are able to maintain blood stream moisture even during extreme heat stress.

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