9781422280331

Cancer and Sickle Cell Disease

celebrate our birthdays once a year, but on a cellular level, we are being born constantly. Some types of cells reproduce primarily when we’re young—bone cells, for instance, do a lot of reproducing when we’re growing, but they slow down once we’ve reached our full height. On the other hand, blood cells are being reproduced all the time. Blood cells are made inside our bones, by what’s called bone marrow. The bone marrow of a healthy person creates about 7 million new blood cells every month. In a process called mitosis , a cell reproduces by dividing into two identical copies of itself. Human cells can divide around 50 to 60 times (the exact number

The stages of cell reproduction, or mitosis.

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