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Reproduction in organisms — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYReproduction in organisms3 Marks
Question
Differentiate between external fertilisation and internal fertilisation with an example for each.
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Answer

External fertilisation
Internal fertilisation
When fusion of gametes (syngamy) occurs outside the body of the organism, it is called external fertilisation.
When fusion of gametes (syngamy) occurs inside the body of the organism, it is called internal fertilisation.
A large number of gametes are released in the surrounding medium by such animals.
The number of ova produced is less, but a large number of male gametes are formed, as they have to travel towards the ovum.
Chances of survival of offspring are less. e.g. frog and bonyfish.
Chances of survival of offspring are high. e.g, birds, human beings, etc.

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