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Telomere and Aging

Why do cells have telomeres?

Why do telomeres get shorter every time a cell divides? What counteracts this shortening?

What role do telomeres play in aging? You may want to do some research into dyskeratosis congenita.

If telomerase makes cancer cells immortal, could it prevent normal cells from aging?

Do you think we could extend the average lifespan by preserving or restoring the length of telomeres with telomerase? If so, does that raise a risk the telomerase also will cause cancer?

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Telomeres and Aging

Why do cells have telomeres?

Telomeres are specialized terminal elements, composed of tandem repetitive sequences at the end of chromosomes. They are composed of GC rich repeats (TTAGGG) that protect the telomere ends and become shortened for every replication cycles. This is known at the end replication problem where the chromosome ends are shortened every cell division and the presence of telomere repeats will prevent this shortening. Telomeres have specific telomeric proteins that bound to it as a function for protection. The telomeric repeat tracts are maintained by a telomere specific reverse transcriptase called telomerase that counteract the loss of terminal sequences during DNA replication. Telomerase act to extend the telomere end and maintained the length of the telomere.

Why do telomeres get shorter every time a cell divides? What counteracts this shortening?

Telomere gets shorter every time a cell divides because of broken DNA at the single stranded chromosome ends leading to resection when telomere are not protected by capping proteins. When the ends of chromosomes are not protected, the telomere ends are damaged ...

Solution Summary

The solution discuses telomere and aging. It describes why cells have telomeres and why they get shorter every time a cell divides.

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