Multiple Choice Questions

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Assertion: Insects visit flowers to gather honey.

Reason: Attraction of flowers prevents the insects from damaging other parts of the plant.

  • If both Assertion and Reason are true and Reason is the correct explanation of Assertion

  • If both Assertion and Reason are true but Reason is not the correct explanation of Assertion

  • If Assertion is true but Reason is false

  • If both Assertion and Reason are false.


D.

If both Assertion and Reason are false.

Insects collect nectar from the flowers. The attraction of flower in plants is not to diverge the insect from damaging other part, but to bring about pollination (i.e. transfer of pollen to the stigma). The pollen grains in insect pollinated flowers are either sticky or provided with spinous outgrowths. The stigma is also sticky. Insect often visiting these flower for nectar and bring about pollination inevidently.


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Assertion : Vegetable oils are fats which are present in plant cells in soluble form.

Reason : Vegetable oils occur only in cells of embryo.

  • If both assertion and reason are true and reason is the correct explanation of assertion

  • If both assertion and reason are true but reason is not the correct explanation of assertion

  • If assertion is true but reason is false

  • If both assertion and reason are false


Double fertilization involves

  • fertilization of the egg by two male gametes

  • fertilization of two eggs in the same embryo sac by two sperms brought by one pollen tube

  • fertilization of the egg and the central cell by two sperms brought by different pollen tubes

  • fertilization of the egg and the central cell by two sperms brought by the same pollen tube.


For self pollination, flower must be

  • unisexual

  • bisexual

  • monosexual

  • asexual


Assertion: Coconut tree is distributed in coastal areas over a large part of the world.

Reason: Coconut fruit can float and gel dispersed over thousands of kilometers before losing viability.

  • If both Assertion and Reason are true and Reason is the correct explanation of Assertion

  • If both Assertion and Reason are true but Reason is not the correct explanation of Assertion

  • If Assertion is true but Reason is false

  • If both Assertion and Reason are false.


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The pollen tube usually enters the embryo sac

  • through one of the synergids

  • by directly penetrating the egg

  • between one synergid and central cell

  • by knocking off the antipodal cells.


When the pollen tube enters through the micropyle, it is termed as

  • chalazogamy

  • mesogamy

  • porogamy

  • none of these


In which one of the following would you expect to find glyoxysomes?

  • Endosperm of wheat

  • Endosperm of castor

  • Palisade cells in leaf

  • Root hairs


Pollen grains are able to withstand extremes of temperature and dessication because their exine is composed of

  • cutin

  • suberin

  • sporopollenin

  • callose


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Plants of which one of the following groups of genera arc pollinated by the same agency

  • Triticum, Cocos, Mangifera

  • Ficus, Kigelia, Casuarina

  • Salvia, Morus, Euphorbia

  • Bombax, Butea, Bauhinia


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