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The Hayflick limit is the maximum number of times a cell can divide, because each time a cell reproduces it loses DNA. This limit was discovered by Leonard Hayflick in the 1960s, who found that chromosomes within the cell had extraneous DNA at their tips (called telomeres). But by the time a cell divides between 52 and 60 times, the telomeres have disappeared and important genetic information is lost, causing aging. Moalem posits that this limit is meant to serve as a safeguard against cancer.
Hayflick limit Quotes in Survival of the Sickest
The Survival of the Sickest quotes below are all either spoken by Hayflick limit or refer to Hayflick limit. For each quote, you can also see the other terms and themes related to it (each theme is indicated by its own dot and icon, like this one:
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Chapter 8
Quotes
Many scientists believe cancer prevention is the “reason” cells have evolved with a limit on the number of times they can reproduce. The flip side to the Hayflick limit, of course—compromise, compromise—is aging. Once cells hit the limit, future reproductions don’t really work and things start to break down.
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Hayflick limit Term Timeline in Survival of the Sickest
The timeline below shows where the term Hayflick limit appears in Survival of the Sickest. The colored dots and icons indicate which themes are associated with that appearance.
Chapter 8: That’s Life: Why You and Your iPod Must Die
...times (52 to 60 times) before the cell division becomes an issue (known as the Hayflick limit ). Every time a cell reproduces it loses DNA; in order to prevent the loss...
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...and growth. There are many lines of defense in the body against cancer, including the Hayflick limit . However, cancer cells have developed an enzyme called telomerase, which can lengthen the telomeres...
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There are other evolutionary explanations for aging mechanisms: the Hayflick limit doesn’t explain why different animals have vastly different life expectancies. Moalem notes that in mammals,...
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