Question

Fusion of one male gamete with egg and other of the same pollen tube with two polar nuclei is
Option A- Triple Fusion
Option B- Vegetative fertilization
Option C- Double fertilization
Option D- Parthenogenesis

Answer 1

In angiosperms plants there are two sperm cells in a pollen tube derived from a single generative cell. When pollen grains stick to the stigma of the plant and begin to germinate and form a pollen tube that extends to ovary through style and the process of fertilization takes place in the female reproductive part of the plant when two sperms are released from the pollen tube.

Complete answer:
After the pollen tubes release two male gametes in the embryo sac out of those two, one male gamete that is present near the egg, fuses with the egg nucleus and it is known as fertilization and it results in the formation of the zygote. The other gametes fuses with the polar nuclei and hence two time fertilization is taking place.

Option A- Triple fusion: It is fusion that takes place between one sperm nucleus and two polar nuclei. This happens during double fertilization in a seed and thus gives origin to the triploid nucleus known as PEN- primary endosperm nucleus.

Option B- Vegetative fertilization: Vegetative fertilization is the other name for triple fusion. Triple fusion is already defined in the above option.

Option C- Double fertilization: It is a complex fertilization in the plants, in this process two sperm or male gametes are involved; one male gamete fuses with the egg cell to form the zygote and other male gamete fuses with the polar nuclei and forms the endosperm. This process of fertilization is called double fertilization.

Option D- Parthenogenesis: In the process of parthenogenesis development of embryo occurs without the fertilization with the sperm. It is a natural form of asexual reproduction.

So the correct answer is Option C- Double fertilization.

Note:
Double fertilization is important as it gives rise to an endosperm that gives nourishment to the developing embryo and it increases the seed viability in angiosperms in this fertilization both male gametes are used that are produced by pollen grains.