Sexual Reproduction

In sexual reproductions, specialized sex cells called gametes are produced. These carry one set of genetic information of the male/ female.

Male mobile  Gamete = sperm

Female stationary gamete = ovum (egg)

Fertilization = the fusion of the male gamete, the sperm with the female gamete, the ovum to produce a zygote.


Zygote = the single cell produced by fertilization

The zygote is able to undergo mitosis to form all the cells of the animal. It forms an embryo.

Fertilisation :-

Once the sperm has reached the ovum, its nucleus must enter the ovum and fuse with the ovum nucleus
- As each gamete has only half the normal number of chromosomes, the zygote formed will have a full number.

Sperm = 23 chromosomes (haploid number)

Ovum = 23 chromosomes (haploid number)

Zygote = 46 chromosomes (diploid number)


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