Multiple Choice Questions

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Advantage of cleistogamy is

  • higher genetic variability

  • more vigorous offspring

  • no dependence on pollinators

  • vivipary


C.

no dependence on pollinators

In cleistogamous flowers, anthers and stigma lie close to each other. When anthers dehisce in the flower buds, pollen grains come in contact with the stigma to effect pollination. Thus, these flowers produce assured seed set even in the absence of pollinators.

The higher genetic variability and more vigorous offsprings are produced to variations obtained by sexual reproduction. Vivipary relates to the birth of young babies from mammals.


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In Zostera, the marine angiosperm, the pollen grains are long ribbon-like and without exine. They have same specific gravity as that of water. How is this feature helpful in their pollination?

  • The pollen grains become unwettable

  • The pollen grains spread over large and they are lighter

  • The pollen grains can float below the surface of water

  • None of the above


Emasculation ensures cross-pollination in

  • staminate flower

  • bisexual flower

  • neuter flower

  • pistillate flower


Endosperm nucleus is

  • n

  • 2n

  • 3n

  • 4n


Cleistogamous flowers are

  • bisexual flowers which remain opened

  • bisexual flowers which remain closed

  • open female flower

  • open male flower


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Identify the correct pair of statements.

I. White kernal of coconut is a free nuclear endosperm.

II. In dioecious plants, autogamy is prevented but geitonogamy occurs.

III. Cleistogamous flowers are always selfpollinated.

IV. Castor is an endospermic seed.

  • II, IV

  • II, III

  • I, II

  • III, IV


Monoecious plant of Chara shows occurrence of

  • antheridiophore and archegoniophore on the same plant

  • stamen and carpel on the same plant

  • upper antheridium and lower oogonium on the same plant

  • upper oogonium and lower antheridium on the same plant


Cross-pollination through insect agent is called

  • anthropophily

  • malacophily

  • entemophily

  • ornithophily


Malacophily is the pollination by

  • insects

  • birds

  • snails

  • mammals


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Perisperm differs from endosperm in

  • being a haploid tissue

  • having no reserve food

  • being a diploid tissue

  • its formation by fusion of secondary nucleus with several sperms


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