D1: Homeostasis — A level

Here are two feedback loop simulators:

• Thermostat simulator - simulates a heater in a room. Be sure to use both the on/off controller and the PID controller.
• Glucose regulation simulator - simulates blood glucose in humans

Experiment with these simulators.

Either write or discuss with your teacher what these simulators show you about homeostasis and negative feedback. Use these points to help you.

• What are the similarities and differences between the way the thermostat controls temperature and the glucose system controls glucose? Describe how the control works.
• How quickly does the (temperature / glucose level) return to normal after a disturbance?
• Explain negative feedback using these systems as examples.