What role do telomeres play in chromosomes?

Telomeres serve a crucial function as protective caps at the ends of chromosomes. Their primary purpose is to prevent the degradation of chromosome ends during DNA replication and subsequent cell divisions. Each time a cell divides, a small portion of the telomere is lost due to the inability of DNA polymerases to completely replicate the ends of linear DNA molecules. By safeguarding these ends, telomeres prevent the chromosomes from being recognized as broken DNA, which could trigger DNA repair mechanisms that might lead to cell death or genomic instability.

In addition, telomeres play a key role in maintaining the structural integrity of chromosomes, contributing to the stability of the genome. As cells experience normal division cycles, the gradual shortening of telomeres serves as a biological clock that limits the number of times a cell can divide, which has implications in aging and cancer biology. Overall, their protective function is essential for the proper maintenance and function of chromosomes throughout the lifespan of a cell.