Final answer:
Telomeres shorten over time, particularly with cell division, leading to cellular aging and reduced regenerative ability. High stress levels can accelerate telomere shortening, further affecting cellular aging. In cancer, telomeres shorten until telomerase is activated, aiding uncontrolled division of cells.
Step-by-step explanation:
Over time, telomeres, which are protective caps at the end of chromosomes, shorten with each cell division. This telomere shortening is closely associated with the natural process of aging.
Most somatic cells lack significant levels of telomerase, an enzyme that can replenish telomeres, and therefore their telomeres continue to get shorter.
Eventually, when telomeres become too short, cells lose their ability to divide and regenerate, leading to the impact on various physiological functions and potentially contributing to age-related diseases like arthritis, memory issues, and certain cancers.
Stress has been found to accelerate the shortening of telomeres, potentially increasing the biological aging of cells. A notable study demonstrated that caregivers of chronically ill children, who were subject to high stress levels, exhibited shorter telomeres compared to controls.
In addition, cancer cells have been noticed to exhibit abnormal telomere dynamics: telomeres shorten until a point when telomerase becomes active, driving the uncontrolled cell division characteristic of cancer.