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biology questions

1,contraception means "birth control",the practice of preventing a woman from becoming pregnant when she has sex, or the methods for doing this

2,mitosis and meiosis

It is not difficult to tell the different between mitosis and meiosis.

Mitosis means nuclear division. This may occur at many body cells for growth and repairing. the daughter cells are genetically identical to the parent cell.

Meiosis is a special cell division for the formation of gametes. The daughter cells contain half no.of chromosome of the parent cell. Therefore it is also called reduction division. After fertification, the total no. of chromosomes in the zygote can be retained.

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