REPRODUCTION IN ANIMALS
What is reproduction in animals? Sexual reproduction involves the fusion of gametes. In animals two individuals are involved, a male and a female. Special organs known as gonads produce gametes.
In males testes produce sperms while in females ovaries produce ova. The fusion of male gamete and female gamete to form a zygote is called fertilization.
There are two types of fertilization.
External and internal Fertilization.
External fertillzation
- Example in amphibians takes place in water.
- The male mounts the female and shed sperms on the eggs as they are laid.
- Eggs are covered by slippery jelly-like substance which provides protection.
- Many eggs are released to increase the chances of survival.
Internal fertilization
- This occurs in reptiles, birds and mammals.
- Fertilization occurs within the body of the female.
- Fewer eggs are produced because there are higher chances of fertilization since sperms are released into the female body.
See also:
METHODS OF FRUIT AND SEED DISPERSAL