Homeostasis

• Chemicals concentration must be in a narrow range such as glucose/Na ions , same with pH and water balance of bodily fluids
• organisms use both chemical and electrical systems to monitor and respond to changes to maintain dynamic equilibrium
• define homeostasis

  the body maintains a dynamic equilibrium but with small fluctuations over a narrow range of conditions
• What helps to maintain dynamic equilibrium

  Receptors, effectors, sensory receptors
• what does a sensory receptor detect

  detects changes in the internal and external environment
• in homeostasis what is it essential to monitor internally?


  the internal environments monitored are the pH of the blood, core body temperature and concentration for urea and sodium ions in the blood
• what do the sensory receptors do

  the information they gain by detecting the change is transmitted to the brain and impulses are sent along the motor neurones to the effectors
• what do the effectors do to maintain dynamic equilibrium?

  effectors are muscles/glands that react to the motor stimulus to bring about a change in response to a stimulus, respond to a need
• What does a negative feedback system aim to do?

  Works to reverse the initial stimulus and restore the conditions back to the base level
• State examples of negative feedback systems controls

  Water balance of the body and temperature control
• there are fewer positive feedback systems than negative
• what’s a positive feedback system what does it do?

  There’s a change in the internal environment, detected by the sensory receptors and effectors are stimulated to reinforce the change to amplify the response.
• example of positive feedback system

  blood clotting cascade