What mechanism do telomeres perform in relation to chromosomes?

Telomeres serve as protective caps at the ends of chromosomes, composed of repetitive nucleotide sequences. Their primary function is to prevent the degradation of chromosomes during DNA replication. With each cell division, telomeres are gradually shortened due to the inability of DNA polymerase to fully replicate the ends of linear DNA. This degradation occurs naturally with increasing age, correlating with the eventual loss of cellular function and contributing to the aging process.

The correct answer reflects this fundamental role: while telomeres protect chromosomes from damage and loss of essential genetic information, they do indeed degrade over time. This mechanism is crucial in regulating cellular lifespan and preventing genomic instability, which can lead to diseases such as cancer. In contrast, the other options imply incorrect functions or outcomes related to telomere behavior, such as maintaining infinite chromosome lifespan or directly replicating DNA, which do not accurately represent the biological reality of telomere function.