How many times a cell could divide

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Q.  How many times a cell could divide
A.           It is fully genetically controlled information  programmed in the cell. The average cell will divide between 50-70 times(The Hayflick limit (Leonard Hayflick in 1961), before programmed  cell death( apoptosis). As the cell divides the telomeres on the end of the chromosome get smaller. due to the telomeres shorteningthrough each division, the
 telomeres will eventually no longer be  present on the chromosome
 .Cancer cells can divide indefinitely since they use an enzyme called telomerase to maintain the telomere length

    e.g.    Meristematic cell go on dividing    but permanent cell   normally don’t divide


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