Endocrine

• How does the endocrine system affect the body?

  It affects almost every cell and organ
• What mechanism is primarily used by the endocrine system?

  Negative feedback mechanism
• What are hormones classified as?

  Chemical messengers of the body
• How do hormones act on target cells?

  They act on specific target cells
• What is the speed of response for the nervous system?

  Milliseconds
• How does the endocrine system transport hormones?

  Via bloodstream to most cells of the body
• What is the duration of effects for the endocrine system?

  Seconds to days; prolonged effects
• Where is the hypothalamus located?

  Between the cerebrum and brainstem
• What does the hypothalamus regulate?

  Temperature, fluid volume, growth
• What type of hormones does the hypothalamus produce?

  Releasing and inhibiting hormones
• What is the role of corticotropin-releasing hormone?

  Stimulates the release of ACTH
• What is the pituitary gland often referred to as?

  The "master gland"
• What are the two divisions of the pituitary gland?

  Anterior and posterior pituitary gland
• What hormone promotes growth of bone and muscle?

  Growth hormone
• What does prolactin stimulate?

  Lactation
• What does TSH stimulate?

  Thyroid hormones production
• What is the function of ADH?

  Reduces urine output
• What does oxytocin act on?

  Uterus and breast
• What hormone does the kidney produce to stimulate calcium absorption?

  1, 25 dihydroxyvitamin D
• What hormone increases red blood cell production?

  Erythropoietin
• What hormones do the ovaries produce?

  Estrogen and progesterone
• What is the role of thymosin?

  Affects maturation of T lymphocytes
• What does the pineal gland secrete?

  Melatonin
• What is the function of thyroid hormones?

  Increase metabolic rate and heat production
• What does calcitonin do?

  Lowers blood calcium levels
• What do chief cells in the parathyroid glands secrete?

  Parathyroid hormone (PTH)
• What is the function of aldosterone?

  Affects sodium absorption and potassium loss
• What does cortisol regulate?

  Metabolism and stress responses
• What is the primary function of the pancreas?

  Releases insulin and glucagon
• What are the two major functions of the pancreas?

  Digestive enzymes and hormone release
• What cells in the pancreas produce glucagon?

  Alpha cells
• What cells in the pancreas produce insulin?

  Beta cells
• What is the normal blood glucose level?

  5 mmol/l
• What are the major glands of the endocrine system and their functions?

  • Hypothalamus: Regulates temperature, fluid volume, growth
  • Pituitary Gland: Master gland; regulates other glands
  • Thyroid Gland: Produces thyroid hormones; regulates metabolism
  • Adrenal Glands: Produce adrenaline, cortisol; stress response
  • Pancreas: Produces insulin and glucagon; regulates blood sugar
  • Ovaries: Produce estrogen and progesterone; menstrual cycle
  • Testes: Produce testosterone; secondary sexual characteristics
  • Thymus: Maturation of T lymphocytes
  • Pineal Gland: Secretes melatonin; sleep/wake cycles
• What are the actions of the major hormones of the pituitary gland?

  • Growth hormone: Promotes growth of bone and muscle
  • Prolactin: Stimulates lactation
  • TSH: Stimulates thyroid hormone production
  • FSH: Stimulates gamete production
  • LH: Stimulates sex hormone production
  • ACTH: Stimulates steroid hormone production
  • ADH: Reduces urine output
  • Oxytocin: Stimulates uterine contractions and milk release
• What are the actions of adrenal hormones?

  • Cortisol: Regulates metabolism, raises blood sugar, anti-inflammatory
  • Aldosterone: Maintains salt/water balance, regulates blood pressure
  • Epinephrine: Involved in stress response
  • Norepinephrine: Acts as neurotransmitter for sympathetic system
• What is the hypothalamic-pituitary-thyroid axis?

  • Hypothalamus releases TRH
  • TRH stimulates anterior pituitary to release TSH
  • TSH stimulates thyroid gland to produce T3 and T4
  • T3 and T4 regulate metabolism and energy
• How does insulin work in the body?

  • Insulin binds to receptor sites on cells
  • Facilitates glucose uptake into cells
  • Lowers blood sugar levels
• What is the role of glucagon in the body?

  • Raises blood sugar levels
  • Stimulates liver to release glucose
  • Opposes the action of insulin
• what does thyrotropin releasing hormone do?

  stimulates the release of thyroid stimulating hormone