Question

Genetic fertilization involves fertilization of male gamete with
(a) Synergid
(b) Oospore
(c) Central cell
(d) Antipodal cell

Answer 1

Hint: Pollen tube carries two male gametes which after entering one of the synergids, release its male gametes into the cytoplasm of the synergids. The fertilization occurs in the embryo sac that results in the formation of the zygote.

Complete Answer:
Genetic fertilization is the process of fertilization of male gametes with the oospore. It consists of various parts that include - synergids, egg, central cee, antipodals, etc. Synergids - They are haploid cells that form finger-like projections. Egg cells and two synergids together constitute the egg apparatus. Egg - Also called oospore, it is the non-motile female gamete that fuses with the male gamete and forms a diploid zygote. Central cell - It is the largest cell of the embryo sac which contains two polar nuclei which fuse to form the secondary nucleus (2n). Antipodals - They are vegetative cells, generally three in number and present at the chalazal end of the embryo sac.

Additional Information:
In the embryo sac, the following events take place:
1. Syngamy:- The fusion of the male gamete with the nucleus occurs which moves towards the egg cell. This results in the formation of a zygote which is a diploid cell.
2. Triple fusion:- The other male gamete moves toward the polar nuclei located in the central cell and fuses with them to produce a triploid primary endosperm nucleus (PEN).
These processes together constitute and called double fertilization in the case of the angiosperms.

So, the correct answer is ‘Oospore'.

Note:
-Embryo sac is a 7-celled, 8-nucleate structure.
-Syngamy and triple fusion are termed double fertilization. Both these events were discovered by S.G. Nawaschin and Guignard in Lilium and Fritillaria.
-Entry of the pollen tube into the embryo sac occurs through the micropylar end, degenerating synergid cells. Many recent studies have shown that the filiform apparatus guides the entry of the pollen tubes.