What Are Senescent Cells?

Senescent cells secrete a large number of molecules, some of them are grossh factors. This is why evolution selected for this venotype. It's not all bad. On the other hand, if you have a pre canceros cell near by, and those growth factors are now being secreted, it's possible that that cancer cell will wake up and start to form a tumor. So again, good for you when you're young, bad for you whenyou 're old.