Home / Biology / Blood glucose and negative feedback

Blood glucose and negative feedback

Compare the virtual feedbacks of diet, hormones, and exercise.

    B15 · Blood glucose and negative feedbackReady
    Compare the virtual feedbacks of diet, hormones, and exercise. You can also experiment with the numbers and controls below.

    Life Sciences · Human Body · Homeostasis / Principles and Exploration

    Blood glucose and negative feedback — principles and investigation

    A negative hormonal feedback occurs in the process of bringing the increased blood sugar level after a meal back to the baseline state. Change the virtual meal amount, feedback strength, and exercise timing, and compare when the control function is turned on and off. This is a concept experiment that reads the degree of deviation from the standard value and the direction of the reaction to reduce it.

    How does it work?

    Meal input is reduced, but if feedback is turned off, high variation remains. When turned on, the deviation is reduced due to the action of insulin.

    Key relationship

    Blood sugar = 90 + x · x, I, Gl ≥ 0

    Try this investigation

    1. Let’s look at the signals between the pancreas’ β and α cells and the liver and muscles. The exercise operates for 20 min from the time of selection.
    2. Record the feedback on and off with the same meal amount and compare blood sugar levels for 180 minutes.
    3. Record the amount of food, timing of exercise, and feedback intensity one by one. Insulin and glucagon are indicators of action, not actual concentrations.

    Interpreting your results

    Why does insulin action increase after blood sugar levels rise?

    Insulin action refers to storage and absorption in the liver and muscles, and glucagon action refers to liver release. The adjustment in the direction of reducing the deviation is called negative feedback.

    Assumptions and limitations

    This is a virtual model for educational purposes, not for judging personal health. 90 mg/dL is for illustration purposes only. x only represents deviations above the standard and does not reproduce hypoglycemia below the standard. α cells are a proxy function that responds to small deviations and exercise demands. Meal input 0.16·meal amount·exp(−0.16t), insulin removal 0.018Ix, hormone disappearance 0.16I·0.15Gl, etc. are integrated by RK4 (1/60 min). It does not predict actual hormone concentrations, diseases, drugs, or individual differences.