system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does your body know when a wound is fully healed and when to stop healing?
gpt
Your body never knows it's fully healed, it just stops sending a healing response when it lacks a signal saying you're hurt. When a cell is damaged it releases calcium, which then triggers a bunch of healing responses. Once the calcium has been removed (dispersed, taken up by other cells, bound to other things) the initial signal is gone, and then the secondary/following signals kinda just peter out. This varies widely based on the location/type/severity of the injury. There is no final "tada" signal saying everything's back up and running.