negative feedback

• your automatic control systems keep your internal environment stable using a mechanism called negative feedback
• when the level of something gets too high or too low, your body uses negative feedback to bring it back to normal
• 1. receptor detects a stimulus - level is too high
  2. the coordination centre receives and processes the information, then organises a response
  3. effector produces a response which counteracts the change and restores the optimum level - the level decreases
• 1. receptor detects a stimulus - level is too low
  2. the coordination centre receives and processes the information, then organises a response
  3. effector produces a response, which counteracts the change and restores the optimum level - the level increases
• the effectors will just carry on producing the responses for as long as they're stimulated by the coordination centre - this might cause the opposite problem making the the level change too much (away from the ideal)
• the receptor detects if the level becomes too different and negative feedback starts again