Endocrine System

• How the endocrine system works 

  • Glands are organs that release small chemicals called hormones.
  • These chemicals are normally released into the bloodstream, allowing them to travel around the body.
  • They can then bind to specific cells that have the correct receptors. 
  • This will bring about some change within the cells.
• True or false? A hormone can only stimulate specific types of cells.

  True

  • A hormone can only stimulate a cell if the cell has the correct receptor for that hormone. 
• Different glands release different hormones.

• Which three of the following statements are true, regarding the the pituitary gland?


  • It's often referred to as the 'master gland'
  • The hormones it releases control what other glands do
  • It releases multiple hormones 
• Which gland releases thyroxine? 

  Thyroid
• What is the role of thyroxine? 


  It regulates metabolism 

  • Thyroxine regulates your metabolic rate. Too much thyroxine will increase your metabolic rate. 
• If the level of thyroxine in the blood is too low, the pituitary gland will release more thyroid stimulating hormone (TSH). 
• What is the role of adrenaline? 

  Stimulates fight or flight response (higher heart rate etc)
• Which organ is adrenaline released from? 

  Adrenal glands 
• Which organ is insulin released from? 

  Pancreas 
• Which of the following are classed as 'sex hormones', and stimulate puberty?

  Testosterone

  Oestrogen
• Which organ is testosterone released from? 

  Testes
• Do the effects of the endocrine system or the nervous system last longer?

  The effects of the endocrine system last longer as the hormones stay in blood for long time (often hours). In contrast, electrical impulses from the nervous system only last a split second.