Body cells

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Q1:How big is a cell?

[Answer]

A human body is made up from about 60 billion cells.

We cannot see any of the cells with the naked eye because they are very small. Cells are too small to be measured in millimetres. They are measured in micrometres. One micrometre is one thousandth of a millimetre.

Many cells, such as those in your cheeks, are about forty micrometres across.