Endocrine system

• What is a hormone?

  Chemical substance produced by a gland carried in the bloodstream to target specific organs.
• Where is the pituitary gland located?

  Base of the brain.
• What is the function of the hormone thyroxine?

  Regulates metabolism, growth and development.
• What is the function of the hormone adrenaline?

  Prepares the body for fight flight. Increases heart rate, blood flow to muscles and blood glucose levels.
• How does insulin regulate blood glucose levels?

  Increase in blood glucose is detected by the pancreas.

  Pancreas releases insulin into the blood stream.

  Insulin travels to the liver causing liver cells to absorb and store glucose from the blood as glycogen.

  Blood glucose levels are reduced.
• What is the function of the hormone insulin?

  Reduce blood glucose levels.
• Are the effects longer in hormones or the nervous sytem?

  Hormones.
• How are hormones transmitted?

  Blood stream.
• What is the speed of a response?


  Slow.
• What does the pituitary gland target?

  Most endocrine glands.
• What does the thyroid gland target?

  Every organ system.
• What does the adrenal gland target?

  Heart, lungs, muscles.
• What does the pancreas target?

  Liver
• What is the pituitary gland also known as?

  The Master Gland
• Explain the role of the pituitary gland

  Hypothalamus detects changes in hormone levels so the pituitary gland will Secrete hormones into the blood stream in order to effect the body.
• Explain negative feedback

  Detects a change, responds to it and returns the condition to normal.
• What does thyroxine control?

  The speed where oxygen and food products react to release energy for the body to use.
• What happens when thryoxine levels are low?

  Hypothalamus releases TRH which causes the pituitary gland to releases TSH. This stimulates the thyroid gland to release more thyroxine.
• What happens when thyroxine levels return to normal?

  Thyroxine inhibits the production of TRH in the hypothalamus and TSH from the pituitary gland. Blood levels are maintained.
• What is the effect on the pancreas if glucose levels are low?

  Insulin is not secreted into the blood.
• What is the effect on the pancreas if glucose levels are high?

  Insulin is secreted into the blood.
• What is the effect on the liver when glucose levels are low?

  Does not convert glucose into glycogen.
• What is the effect on the liver when glucose levels are high?

  Converts glucose into glycogen.