Ask Me Everything5

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How many body cells do you have?

Everything in your body, from your skin to your intestines, is madę up of microscopic cells. Scientists estimate that a body contains around 100 trillion cells, but no one knows exactly how many. The number varies according to the size of the person and constantly changes as old cells die and new cells are madę.

,^d blood

Two    _duced

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Centromere

Nucleus

Nuclear

membranę

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Use the microtubules to puli apart the chromosomes so that each chromatid travels to a different half of the celi.

Everybody starts life as a single celi—

the fertilized ovum, or egg. Within 24 hours of fertilization" the egg divides into two identical cells, which continue to divide as they travel safely to the womb.

In numbers

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How to: divide a celi

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Microtubule pulls chromosome

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