Which part of the living system did you change?
Labs / Biology
Thermoregulation
Drag the environment thermometer to plunge the body into the Arctic or the desert, then push its activity up. The body senses how far its core has drifted from 37°C and fights back with shivering, sweating, and changes in skin blood flow. Switch those responses off one at a time to see the negative-feedback loop break down.
Labs / Biology / Thermoregulation
Thermoregulation
Drag the environment thermometer to plunge the body into the Arctic or the desert, then push its activity up. The body senses how far its core has drifted from 37°C and fights back with shivering, sweating, and changes in skin blood flow. Switch those responses off one at a time to see the negative-feedback loop break down.
Why it matters
Why explore this?
Living systems are connected and constantly changing. This model makes one biological process visible so you can test how its parts affect one another.
Explore
Try the model
Core 37.00 °CGain 0 WLoss 0 WResponse Balanced
Investigate
Questions to test
Predict first, try it in the model, then use what you observe to answer.
What to try
- In the Arctic, why does the skin turn pale and blue before the body starts to shiver?
- Turn off vasoconstriction in the cold. How far does the core fall, and can shivering alone hold the line at 37°C?
- Crank activity to a sprint in the desert. Which response does the body lean on hardest to dump all that extra heat?
- Disable sweating on a hot day. How quickly does the core climb toward the danger zone > 40°C?
- When gain and loss finally match, where does the core settle — exactly on the set point, or a little above or below it? What does that say about feedback control?
Explain
Make sense of what happened
Explain the process as a chain: a change happens, the system responds, and that response affects what happens next. Use an observation from the model as evidence.
Check
Before you leave
How did the system respond?
How would you explain that response?
If you can answer all three using evidence from the model, you understand the main idea. If not, return to Explore and change one setting at a time.