Solution :
Differences between internal and external fertilisation
Internal fertilization
Fertilisation takes place outside the female’s body
A large number of male and female gametes are released in the surrounding medium (like water).
Organisms that use external fertilization to reproduce must either live in the water or return to the water for reproduction.
As the chance of fertilization in water is generally less, a large number of gametes are released.
Examples: Fish, Amphibians etc.
External fertilization
Fertilization takes place inside the female’s body.
Male gametes are released inside the female body by a copulatory organ.
Animals that have internal fertilization have completely transitioned to life on land.
The number of gametes produced in this mode is relatively less.
Examples: Reptiles, Birds, Mammals, etc.