Explain the process of fertilization in plants.

Explanation

After entering into the embryosac, the pollentube bursts and releases the two male gametes in to the cytoplasm ofthe synergid. One of the male gametes moves towards the egg cell and the riucleus of the male cell fuses with egg nucleus, thus completing the syngamy or fertilisation. This results in the formation of a diploid cell, the zygote. The other male gamete moves towards the two polar nuclei, located in the central cell and fuses with them to produce a triploid primary endosperm nucleus. In this, the fusion occurs between three nuclei so called Triple fusion. Since two types of fusions syngamy and Triple fusion occurs in an embryosac, the phenomenon is termed as double fertilization. The primary endosperm cell develops into endosperm while the zygote developes into an embryo.