If cells duplicate and grow exponentially, why dont we?

Question

Why dont we go from, for example, 3 billion cells to 6 billion. Say the body stops, or slows, how does the body m ow when to do that?

In: 2

Answer 1

Cells do not duplicate exponentially. Cells divide when they get damaged, making a new healthy cell, and the damaged cell dies off (via the lysosomes in the cell)

Inside each cell is a chemical “chain” called a telomerase chain, and every time a cell divides, one “rung” of this chain is broken/not copied over. When the telomerase chain is gone, the cell will no longer divide when damaged, which is why we eventually grow old and die: our cells are pre-programmed to only have a certain lifespan, they do not divide forever