Which statement about the automatic control systems that maintain homeostasis is correct?
They act after a change has been detected, to reverse it
They keep every internal condition exactly the same at all times
They respond only to changes outside the body of the organism
They are all controlled by hormones carried around in the blood
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.