system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is that when you touch an open wound (or the “white meat”) under your skin with your finger, it burns?
gpt
Because the nerves that bring sensations like pressure, heat and cold to your brain get the info from special structures around nerve endings that are deep in your skin. If you touch an open wound you stimulate directly your nerves and give them a much greater stress. The other case where this happens is when your skin is removed by fire and the nerve endings are exposed to the air so the sensation is similar.  
Think of it like a short circuit.