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Sexual Reproduction

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Sexual reproduction


Sexual reproduction is a type of reproduction in which there is formation and fusion of gametes.
It mostly involves two parents. The male produces male gametes – Sperm and the female produces female gametes –Ova. When male and female gametes are produced by different organisms, they are called unisexual or dioecious e.g. frog, dog, man, cockroach etc.

When male and female sex cells are present on the same individual, such animals are called bisexual or monoecious e.g. Leech (Hirudinaria), Earthworm, Taenia.


Types of Sexual Reproduction

Sexual reproduction may be of two types: Amphigony and Parthenogenesis.

Amphigony : In this type of reproduction two gametes fuse to form a zygote.

Parthenogenesis : It is a type of monoparental reproduction in which an unfertilized egg develops into a fully formed haploid organism. It occurs in some insects e.g. honey bee, wasps.

Processes involved in sexual reproduction

Gametogenesis : These are the haploid cells produced by gonads viz. testes and ovary. Testis produces sperms and the ovary produces  ovum or egg.
The process of formation of gametes is called gameteogenesis.

Fertilization : The process of fusion of male and female gametes is called fertilization.




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