Question

Definition of external and intyernal fertilization in animals

Answer 1

Internal Fertilization :

The fertilization process occurs within the body of a female is called internal fertilization. It is a specialization for the protection of egg, but it depends on the birth method . Reptiles and birds have thick shell, covering the egg to protect it from dehydration and destruction. However, fertilization occurs inside the body otherwise, sperm has to enter through a thick wall.Animals such as mammals also have internal fertilization, where embryo develops inside mother, which enhances the protection to the embryo1.Internal fertilization facilitates the survival of the embryo, selective fertilization, and longer protection and minimizes the wastage of gametes.

External Fertilization

In external fertilization fusion of sperm and egg occurs externally of the female body. External fertilization needs water to facilitate their fertilization, so it occurs in wet environments. Female and male gametes are released to the water, and male gamete is mostly mobile. This type of fertilization can be seen in lower plants. The advantage of external fertilization is that it produces a large number of offspring due to the external hazards. So survival of the embryo is comparatively lower. Amphibians and fish are examples for these types of animals

Answer 2

Hey mate here is your answer☺

The type of fertilization in which the male and the female gamete fuses inside the female body is called internal fertilization.

The type of fertilization in which the male and female gamete fuses outside the female body is called external fertilization.

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