Boxi Learn › Biology › Stage 4 · Systems and Argument
The body's thermostat
BIO-2 Structure fits functionX-3 Look from another sideX-4 Explain it to someone
What many people think
Negative feedback means something bad, and a healthy body's levels never move.
The idea
Body temperature and blood sugar stay near a set point because any change switches on a response that pushes it back: negative feedback.
Explain it
A friend says "negative feedback" must be something bad, and that a healthy person's temperature never changes. Using what happened when you stepped into the cold, explain what negative feedback really is and why the number still moves.
Try at home
Measure your temperature under the tongue when you wake up, after lunch and in the evening, three days in a row, and plot it. Does it stay at exactly 37.0? (Use the same thermometer; wait 15 min after eating or drinking.)