How do telomeres contribute to chromosome stability?

Telomeres are repetitive nucleotide sequences located at the ends of chromosomes. Their primary function is to protect the ends of chromosomes from deterioration or fusion with neighboring chromosomes. When cells divide, the DNA replication process often cannot fully replicate the ends of linear chromosomes, leading to potential loss of important genetic information. Telomeres act as a buffer, ensuring that even if some of the DNA is lost during replication, the essential genes remain intact.

By preventing chromosomal fusion, telomeres maintain the integrity and stability of chromosomes. If telomeres were not present, the chromosome ends could be recognized by the cell as damaged DNA, potentially leading to inappropriate repair mechanisms that could cause chromosomes to fuse together. Such fusions can result in genomic instability and may lead to various diseases, including cancer.

The other options do not accurately describe the primary role of telomeres. Gene expression is related to how genes are turned on or off, DNA repair involves processes that fix damaged DNA but is not the main function of telomeres, and inhibiting cell division is not a function attributed to telomeres, which instead play a role in regulating the lifespan of cells through the maintenance of chromosome integrity.