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Science

Reproduction

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Sexual reproduction produces offspring that resemble their parents, but are not identical to them. Asexual reproduction produces offspring - clones - which are genetically identical to their parents.

Plants can be cloned artificially using cuttings or tissue culture. Animals can be cloned using embryo transplants or fusion cell cloning. Genetic information from one species can be transferred to another species using genetic modification.

Sexual reproduction

Organisms have sex cells called gametes. In human beings, the male sex cells are called sperm and the female sex cells are called eggs or ova.

Fusion

Sexual reproduction happens when a male gamete and a female gamete join. This fusion of gametes is called fertilisation. Sexual reproduction allows some of the genetic information from each parent to mix, producing offspring that resemble their parents but are not identical to them. In this way, sexual reproduction leads to variety in the offspring. Animals and plants can reproduce using sexual reproduction.

the female egg and the male sperm fuse to create a zygote cell which then turns into an embryo. 23 chromosomes from the male and female each make 46 chromosomes in 23 pairs

Process of fertilisation

In human beings, each gamete contains 23 chromosomes, half the number found in the other cells of the body. When the male and female gamete fuse, the new embryo contains the full 46 chromosomes – half from the father and half from the mother.

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