1. what is cell division?
2. what is nucleus?

When a cell reaches maturity, it divides to give rise to new cells of the same type. This process by which a cell divides to give rise to new cells is known as cell division.

The nucleus is the largest organelle present in the eukaryotic cells. In mammalian cells, the size of the nucleus typically varies from 11 to 22 µm in diameter. It is spherical in shape.

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