Cellular Self-Sacrifice

A astrocyte (kind of glial cell that provides nutrients to neurons) stained for particular proteins. The purple blue ovals are the nuclei where the DNA is.

We naturally think of death as something awful, a scourge to be dreaded and put off for as long as possible. But biological death has its positive side. Think of self-sacrifice—death for the good of others. That kind of death we think of as altruistic, even noble, attributing it to heroes or saints. And most of us don’t realize that such self-sacrifice is written into our bodies, at the deepest levels of our being.

The process is called apoptosis, in which cells kill themselves from within. It is not death due to overwhelming damage—that’s another process and called by another name. Rather it is a programmed process whereby cells self-destruct. They shred their DNA, internal organelles (specialized parts of cells) condense, and membranes bleb (blister). Then scavenger cells come by and clean up the remnants for recycling.

Read more