Describe the various steps involved in the sexual reproduction in animals. Draw labelled diagrams to show the fertilisation of an ovum (or egg) by a sperm to form a zygote.
The sexual reproduction in animals takes place in the following steps:
(i) The male parent produces male gamete called sperms. The sperm is a small cell with a long tail (flagellum) for movement.
(ii) The female parent produces female gamete called ova which is much bigger cell than the sperm, having a lot of cytoplasm.
(iii) The sperm enters into the ovum and fuses with it to form a new cell called zygote and this process is called fertilisation.
(iv) The zygote then divides again and again to form a large number of cells and ultimately the zygote grows and develops to form a baby.