What function do telomeres serve during cell division?

Telomeres serve the crucial function of protecting the ends of chromosomes. They are repetitive DNA sequences located at the tips of linear chromosomes, and their primary role is to prevent the chromosomes from fraying or sticking to each other. This protective mechanism ensures that the genetic information contained within the chromosomes is maintained during cell division.

Each time a cell divides, a small portion of the telomere is lost, which eventually limits the number of times a cell can divide—a phenomenon known as the Hayflick limit. This is why telomeres are significant in aging and in the cellular processes that prevent uncontrolled cell growth, such as cancer. When telomeres become critically short, it triggers cellular senescence or apoptosis, preventing further cell division and protecting against tumor formation.

While telomeres are related to the number of times a cell can divide (which might suggest unlimited divisions), their main and specific function is to safeguard chromosomal integrity rather than directly encouraging cell division or causing apoptosis or mutations.