Principles

2.6.2 Control of water & ion content

Principles

  1. Automatic control systems in the body keep conditions inside the body relatively constant

  2. Control systems

    1. Receptors detect stimuli
    2. Coordination centres receive & process information from receptors
    3. Effectors bring about responses

  3. Receptors

    1. Eyes are sensitive to light
    2. Ears are sensitive to sound and spacial orientation
    3. The tongue & nose are sensitive to chemicals
    4. The skin is sensitive to touch, pressure, pain and temperature change
    5. The brain is sensitive to the temperature and water concentration of the blood
    6. The pancreas is sensitive to the glucose concentration of the blood

  4. Coordination centres

    1. Coordination centres include the brain & spinal cord and the pancreas
    2. Many processes are coordinated by hormones, which are produced by glands and normally transported to their target organs by the bloodstream

  5. Controlled conditions

    1. Core body temperature
    2. Water content of the body
    3. Ion content of the body
    4. Blood glucose levels