Though hen and frog both are oviparous but they have different types of fertilisation. Justify.
In hen, internal fertilisation takes place. The fertilised egg develops into an embryo inside the body. But development of chick from the embryo takes place outside the body. On the other hand, frog shows external fertilisation. The female frog discharge many eggs in the water and the male frog discharge sperms. The sperms swim to the eggs and fertilise them.
