Endocrine system

• Thyroxine


  Functioning properly
• Follicle Stimulating Hormone


  • Glands which produces it: Pituitary gland
  • Position in the body: Part of the brain
  • Target organs: Ovaries, testis
  • Response of the body: Follicles develop in the uterus, increase sperm production
  • Abnormal functions: Activity of either glands is effected if the pituitary is not functioning properly
• Lutenizing Hormone


  • Glands which produces it: Pituitary gland
  • Position in the body: Part of the brain
  • Target organs: Ovaries, testis
  • Response of the body: Causes ovulation and testosterone release
  • Abnormal functions: Activity of either glands is effected if the pituitary is not functioning properly
• Antiduretic Hormone


  • Glands which produces it: Pituitary gland
  • Position in the body: Part of the brain
  • Target organs: Kidney
  • Response of the body: Causes kidney to reabsorb water
  • Abnormal functions: Activity of either glands is effected if the pituitary is not functioning properly
• Prolactin


  • Glands which produces it: Pituitary gland
  • Position in the body: Part of the brain
  • Target organs: Breasts
  • Response of the body: Causes the breasts to produce milk
  • Abnormal functions: Activity of either glands is effected if the pituitary is not functioning properly
• Thyroxine


  • Glands which produces it: Thyroid
  • Position in the body: Neck
  • Target organs: none
  • Response of the body: Controls basic metabolism and growth rate
  • Abnormal functions: Lack: Dwarfism, mental retardation, Excess: Hyperactivity
• Insulin


  • Glands which produces it: Islets of Langerhans
  • Position in the body: Pancreas
  • Target organs: Liver
  • Response of the body: Decreases level of sugar in blood
  • Abnormal functions: Lack: Diabetes mellitus
• Glucagon


  • Glands which produces it: Islets of Langerhans
  • Position in the body: Pancreas
  • Target organs: Liver
  • Response of the body: Increases levels of sugar in blood
  • Abnormal functions: Lack: Diabetes mellitus
• Endocrine system


  A collection of glands that secrete chemical messages called hormones
• How the endocrine system works

  1. Hormones are passed through the blood to arrive at a target organ

  2. Target organ has cells possessing the appropriate receptor
• Hormone


  A specific messenger molecule built and secreted by a group of specialised cells called an endocrine gland
• Types of glands in the body

  • Exocrine glands - secrete products through ducts (e.g. sweat glands, salivary glands)
  • Endocrine glands - secrete hormones directly into the bloodstream (ductless glands)
• Adrenaline


  • Glands which produces it: Adrenal Gland
  • Position in the body: Above kidneys
  • Target organs: Vital organs, liver, heat, etc.
  • Response of the body: Fight or flight actions by increasing heartbeat & sugar level
  • Abnormal functions: -
• Oestrogen


  • Glands which produces it: Ovary
  • Position in the body: Abdomen
  • Target organs: Female reproductive organs
  • Response of the body: Controls secondary sexual characteristics E.g. Growth of hair, breasts, etc.
  • Abnormal functions: Causes delay of these changes
• Progesterone


  • Glands which produces it: Ovary
  • Position in the body: Abdomen
  • Target organs: Pituitary Gland
  • Response of the body: Prevents uterine wall contraction
  • Abnormal functions: When low, menstruation occurs
• Testosterone


  • Glands which produces it: Testis
  • Position in the body: in scrotum
  • Target organs: Male reproductive organs
  • Response of the body: Controls secondary sexual characteristics e.g. deepening of voice
  • Abnormal functions: causes delay of changes
• Thyroid Stimulating Hormone


  • Glands which produces it: Pituitary gland
  • Position in the body: Part of the brain
  • Target organs: Thyroid
  • Response of the body: Controls thyroid
  • Abnormal functions: Activity of either glands is effected if the pituitary is not functioning properly