Internal Fertilisation

External Fertilisation

What is it?

Sperm meets the egg while the egg is still inside the female body

Sperm meets the egg while the egg is outside the female body

Conditions?

Need to have protection for the developing egg

Usually occur in wet environment. Male and female releases their gametes into their surrounding

Good?

Protection for the embryo as it develops within the mother

Usually result in production of large number of offspring

Bad?

Limited number of offspring

The presence of predators reduces the survival of the eggs

Who?

Mostly reptiles and mammals

Mostly amphibians and fish