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Name: Taylor
Status: Student
Grade:  9-12
Location: NJ
Country: United States
Date: November 2008

Why don't cells continue to grow indefinitely?

Every time a cell divides, the tips of the chromosomes (telomeres) are shortened until the chromosomes can no longer replicate thus ending the cells ability to divide. This takes about 50 cell divisions and is one of the causes of aging. This process does not occur in cancer cells or sex cells and that is why they are immortal.

Ron Baker, Ph.D.

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