Define external fertilization?

Define external fertilisation. Mention its disadvantages.

Differentiate between external fertilization and internal fertilization.

Write any two differences between external fertilization and internal fertilization.

Give an example each of animal ashowing external fertilization and another of internal fertilization.

Why do gametes produced in large numbers in organisms exhibit external fertilization?

Given below are a few statements related to external fertilization. Choose the correct statements. The male and female gametes are formed and released simultaneously Only a few gametes are released into the medium. Water is the medium in a majority of organisms exhibiting external fertilization. Offspring formed as a result of external fertilization have better chance of survived than those formed inside an organism.

Why animals which undergo external fertilization such as frog and fish lay eggs in hundreds while a hen lays only one egg at a time?