In internal fertilization inside the female body the syngamy of gametes takes place after insemination through copulation.
Internal fertilization is observed in mammals, birds, and some plants such as bryophytes and pteridophytes.
Internal fertilization occurs in 3 ways –
Ovoviviparity – eggs retained in the female body, hatched when fully developed. For example – snakes, sharks, rays etc.
Oviparity – egg-laying. For example – Turtles, crocodiles etc.
Viviparity – offspring develop within the female body. For example – human beings, dogs etc.
While in external fertilization outside the female body, syngamy of gametes takes place.
Mostly the syngamy of gametes takes place in water bodies.
In external fertilization multiple gametes are released into the external environment.
For example – Algae, Fish, Amphibians etc.
Final Answer :
Hence, in internal fertilization, fertilization takes place inside the body while in external fertilization it is external.
