It even sends signals that indicate trouble elsewhere. With fever, the skin perspires. When one is frightened, it pales. When one is embarrassed, it blushes. The body repairs itself.
Broken bones mend and become strong once again.
Skin lacerations heal themselves. A leak in the circulation can seal itself. The body renews its own outdated cells. The average red blood cell, for instance, lives about 120 days. Then it is replaced by a newly regenerated cell.