Question

What is a telomere? What happens to telomeres each time DNA is replicated? How do cells prevent this from occurring?

Answer 1

Telomeres are protective sequences of nucleotides found at the ends of chromosomes,Which become shorter every time a cell divides.
A gradual degeneration of an organism occurs, resulting in ageing.
However, some cells are able to replenish their telomeres using the enzyme telomerase. 
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