The endocrine system

• Outline the function of the endocrine system.


  The endocrine system provides a chemical system of communication via the blood stream.

  This is because it comprises of glands that secrete chemicals known as hormones.

  These hormones travel through the blood stream until they reach their target sites.

  Once reached, they bind to their specific receptors.

  Once bound, they regulate many bodily functions such as growth and sleep.
• Identify endocrine glands, the hormones they secrete, and what role these hormones play.

  Pituitary gland. Located in the brain. Known as the ‘master gland’ as it secretes hormones that trigger other glands in the body to secrete hormones. It also secretes the growth hormone. This promotes physical growth and muscle mass.
• Identify endocrine glands, the hormones they secrete, and what role these hormones play.

  Pineal gland. Located in the brain. Secretes the hormone melatonin. This regulates the sleep/wake cycle by causing feelings of tiredness.
• Identify endocrine glands, the hormones they secrete, and what role these hormones play.


  Adrenal glands. Located above the kidneys. These secrete the hormone adrenaline. This produces the physiological changes seen in the fight or flight response e.g. increased breathing and heart rate.
• Identify endocrine glands, the hormones they secrete, and what role these hormones play.


  Ovaries. Located in the female reproductive system. These secrete the hormone oestrogen. This produces female sex characteristics (e.g. breast growth) and gender characteristics (e.g. increased empathy).
• Identify endocrine glands, the hormones they secrete, and what role these hormones play.


  Testes. Located in the male reproductive system. These secrete the hormone testosterone. This produces male sex characteristics (e.g. facial hair) and gender characteristics (e.g. increased aggression).