hormonal negative feedback systems

• The endocrine system secretes hormones into the bloodstream from glands throughout the body
• Hormones produce an effect on specific target organs in the body
• Homeostasis is the maintenance of steady conditions in an organism
• Homeostasis involves keeping conditions such as water concentration, temperature, and glucose concentration as constant as possible
• Control systems that keep such conditions constant are examples of homeostasis
• A negative feedback mechanism is an important type of control found in homeostasis
• Negative feedback control systems respond when conditions change from the ideal or set point and return conditions to this set point
• There is a continuous cycle of events in negative feedback
• General stages in negative feedback:

  • If the level of something rises, control systems reduce it again
  • If the level of something falls, control systems raise it again
• An example of negative feedback is the control of body temperature
• Body temperature is controlled by the hypothalamus in the brain
• If the body gets too hot, it begins to sweat to reduce temperature

  • If the body gets too cold, it begins to shiver to raise the temperature