Feedback systems

• In animals, conditions such as water concentration, temperature and glucose concentration must be kept as constant as possible
• Control systems that keep such conditions constant are examples of homeostasis; this is the maintenance of constant internal conditions in an organism
• a negative feedback mechanism is an important type of control which is found in homeostasis
• a negative feedback control system responds when conditions change from the ideal or set point and returns conditions to this set point
• Generally:

  • if the level of something rises, control systems reduce it again
  • if the level of something falls, control systems raise it again
• Negative Feedback flowchart:

  
• An example of negative feedback is the control of body temperature. Body temperature is controlled by the hypothalamus in your brain, and if your body gets too hot, your body begins to sweat to try and reduce it. Conversely if the body gets too cold, it begins to shiver to try and raise the temperature.