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Homeostasis and Control Systems

17 cards

  1. What is homeostasis?

    The regulation of the internal conditions of the body to keep them constant.

  2. Name three conditions that the body controls.

    Body temperature, blood glucose concentration and water content.

  3. At what temperature is the human body kept?

    About 37 °C.

  4. Why must body temperature stay constant?

    Enzymes work best at an optimum temperature.

  5. What happens to enzymes if the body gets too hot?

    They denature and stop working.

  6. What does a receptor do?

    Detects a change in a condition.

  7. What does a coordination centre do?

    Receives the information and decides on the response.

  8. What does an effector do?

    Carries out the response.

  9. Give two examples of coordination centres.

    The brain and the pancreas.

  10. What is negative feedback?

    A response that reverses a change and brings the condition back to normal.

  11. What happens if the condition is too high in negative feedback?

    The response makes it fall.

  12. What happens if the condition is too low in negative feedback?

    The response makes it rise.

  13. Why is the water content of the blood controlled?

    Osmosis would make cells gain or lose water.

  14. Why is blood glucose controlled?

    Cells need a supply of glucose for respiration.

  15. Is homeostasis automatic?

    Yes, you do not have to think about it.

  16. A negative feedback loop with a pointer marked X to the fourth box. Name the part of the control system marked X.

    The effector. It carries out the response, such as a muscle contracting or a gland releasing a chemical.

  17. A negative feedback loop with no labels. Name each stage of a negative feedback loop. The same loop with every box labelled.

    Change from normal, receptor, coordination centre, effector, return to normal. The response reverses the change, which is negative feedback.