A response lowers an internal condition below its optimum. The control system is functioning. What should happen next?
The low value becomes the new optimum and no further response is possible.
The effectors permanently stop receptors detecting any additional changes.
The coordination centre changes the external environment to match the low value.
The new deviation is detected and a response acts in the opposite direction.
40 exam-style questions on AQA GCSE Biology 5.1 Homeostasis, covering 5.1 Homeostasis. Each one has a worked solution and a mark scheme showing where the marks go.