Several mechanisms regulate cell lifespan, including:
1. Apoptosis: Programmed cell death ensures that cells are removed when they are no longer needed or are damaged. 2. Cell Cycle Control: Regulatory proteins and checkpoints in the cell cycle can signal when a cell should divide or die. 3. Stem Cell Niches: Stem cells in tissues like the bone marrow or gut continuously produce new cells to replace the old ones.
