NEET BIOLOGY

Detailed explanation-1: -One of the male gametes fertilizes the egg resulting in the formation of a zygote and the other unites with 2 polar nuclei for the formation of an endosperm.

Detailed explanation-2: -The pollen grain represents the male gametophyte generation; it contains two male nuclei: a generative nucleus and a tube nucleus.

Detailed explanation-3: -Two nuclei at the micropylar end form egg and a synergid, eight fuse in the centre of the cell to form a polar nucleus and the remaining six at the chalazal end formed antipodals. In the mature embryo sac three nuclei form egg apparatus.

Detailed explanation-4: -Two sperm cells fertilize two female gametophytic cells: the egg cell and the central cell (Fig. 1; Appendix). After fertilization, the embryo develops from the fertilized egg cell and the central cell gives rise to the endosperm, which nourishes the embryo for its development.

Detailed explanation-5: -megagametophyte (”female” gametophyte): ma-ture embryo sac, most commonly consisting of seven cells and eight nuclei (two synergid cells, an egg cell, three antipodal cells, two polar nuclei).