Which of the following is not a part of pre- fertilisation and fertilisation events?

Embryogenesis.

Pre fertilisation events include all the events of sexual reproduction prior to the fusion of gametes. The two main pre-fertilisation events are gametogenesis and gamete transfer. Gametogenesis refers to the process of formation of the two types of gametes – male and female. Gametes are haploid cells.

After the formation of male and female gametes, must be physically brought together to facilitate fusion (fertilisation). In a majority of organisms, male gamete is motile, and the female gamete is stationary. Exceptions are a few fungi and algae in which both types of gametes are motile. A large number of the male gametes, however, fail to reach the female gametes. To compensate this loss of male gametes during transport, the number of male gametes produced is several thousand times the number of female gametes produced.

The most vital event of sexual reproduction is perhaps the fusion of gametes. This process called syngamy results in the formation of a diploid zygote. The term fertilisation is also often used for this process. The terms syngamy and fertilisation are frequently used though, interchangeably.

Embryogenesis is the event of post fertilisation. It refers to the process of development of embryo from the zygote. During embryogenesis, zygote undergoes cell division (mitosis) and cell differentiation.