Endocrine system

• Exocrine glands 


  Release products into ducts (tubes)

  eg salivary, sweat ,tear ,gastric glands
• Endocrine glands 


  Ductless gland that produces hormones which are released into bloodstream
• Hormone 


  chemical messenger produced by an endocrine gland and carried by the bloodstream to another part of the body where it has a specific effect
• Hormones 


  Most hormones are made of protein, some hormones are steroid based (especially male and female reproductive hormones), a steroid is a form of lipid.
• Location of principal endocrine gland

  1. Hypothalamus
  2. pineal
  3. pituitary
  4. parathyroids
  5. thyroid
  6. thymus
  7. adrenal
  8. pancreas
  9. testis

  
• Pituitary gland

  1. Master gland- produces many hormones that regulate other endocrine glands
  2. located beneath brain
  3. produces follicle stimulatING hormone (FSH) and luteinising hormon (LH)
  4. produces growth hormone
• FSH

  Causes production of sperm and egg Gametes
• LH

  causes ovulation in females
• Hypothalamus

  1. Links nervous and endocrine systems
  2. its hormones control pituitary gland in response to messages from brain
  3. it’s above pituitary gland
  4. produces anti diuretic hormone
• ADH (anti diuretic hormone)

  causes water to be RDA sorted in kidneys (osmoregulation)
• Pineal

  1. Located in brain
  2. produces melatonin
  3. responsible for sleep patterns, sexual maturity and ovulation
• Thyroid

  1. Located in trachea
  2. produces thyroxine with controls metabolism
• Thyroxine deficiency symptoms

  • (children) Low metabolic rates and retarted mental and physical development -cretinism
  • (Adult) reduced metabolic rate- tiredness no energy, weight gain -myxoedema
• Thyroxine deficiency measures

  New born babies can be given thyroxine.

  adults can take thyroxine tablets or iodine
• Thyroxine excess symptoms

  Increased metabolic rate which causes bulging eyes, weight loss, hunger etc. Graves’ disease
• Thyroxine excess corrective measures

  Graves’ disease can be cured by surgucally removing part of the thyroid or radioactive iodine
• parathyroids

  Onky 4 embedded in thyroid gland, produce parathormone which stimulates release of calcium from bones into blood plasma
• Thymus

  Located in upper chest, produces thymosin which causes white blood cells to mature and become active
• Adrenals

  On top of kidneys, produce adrenaline
• Pancreas

  A dual function gland, its both endocrine and exocrine

  exocrine: produces amylase which travels to duodenum

  endocrine: produces insulin which reduces blood glucose levels
• Ovaries

  Produce oestrogen and progesterone
• Testes

  Produce testosterone
• Hormone supplement insulin

  Insulin is a vital hormone for reducing blood glucose levels causing cells to absorb glucose from the blood. must be given to people with diabetes type 1, as they cannot make the hormone insulin. The islets of langerhans isn’t producing insulin in people with type 1 diabetes.
• Hormone supplement anabolic steroids

  These are drugs that help build up protein quickly in muscles.

  Steroids are hormones which are a type of lipid.

  They damage the liver and potentially cause infertility

  problems.