Question

One plant produces only female white flowers, if it produces pink flowers in the next generation then which one of the following is possible?
(A) Double fertilization
(B) Self pollination
(C) Cross pollination
(D) No fertilization

Answer 1

Hint:In the flowering plants, the pollination takes place to produce the fruits. In this it may happen in two ways as self and the cross pollination. In cross pollination, the gametes undergoing the pollination is from the different sites and hence it may result with the new characteristics.

Complete answer:
Cross pollination is defined as the exchange of pollen grains from the male reproductive organ (an anther or a male cone) of one plant to the female reproductive organ (a shame or a female cone) of another plant. This mainly takes place by means of the transmission by the wind, water, insects, animals etc. In this situation, the pollen grain from the pink flower must have entered into the ovule of the white flower. This case produces the pink flower in the white plant under consideration.

The other options, double fertilization is the complex method of pollination which mainly takes place in the blooming plants (angiosperms). This method includes the joining of a female gametophyte mega gametophyte or the eggs in the ovum with the two male gametes, pollen grains. There are two sorts of self-fertilization: In autogamy, the pollen grain is moved to the ovum of the same flower. In geitonogamy, pollen is moved from the anther of one blossom to the ovum of another bloom on a similar blooming plant. This produces only the white flowers since the pollination takes place in the same plant. In the case of no fertilization, there will be no pollen grains entered into the ovum and hence the white flowers remain.

Thus the correct answer is option (C)

Note: In the process of cross pollination, if the pollen grains are transmitted by the wind it is called anemophily. If it is transmitted by the water, it is called hydrophilly and if it is transmitted by the animals, it is called as the zoophily. In the case of zoophily, the pollen grains may stick to the animal fur.