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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: Cuscuta is an example of holoparasite.
Reason: Cuscuta does not depend on other plants for nutrition requirements.
✓

Answer

  1. Assertion is true but reason is false.

Explanation:

Holoparasites are those parasites which are completely dependent on the host for all their requirements, e.g. Rafjlesia, Cuscuta. Along with other nutritional requirement Cuscuta is known to receive even the flower inducing hormone or florigen from the host. It is, therefore, short day plant in con tact with short day plant host and long day plant in contact with long day plant host

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