CH. 6 Endocrine System Flashcards
- What are endocrine glands derived from?
epithelial tissue
- What are the primary endocrine organs?
and which is the main endocrine organ?
- hypothalamus* and pituitary gland
- pineal gland
- thyroid gland and parathyroid gland
- thymus
- adrenal glands
- pancreas
- gonads
- What are the hormones of the posterior pituitary?
- Antidiuretic hormone (ADH)
- also called vasopressin
- aids in water balance and osmolarity (controls the amount of aqua pores in distal convoluted tubules and aquaduct - oxytocin
- milk ejection
- What is the purpose of the hypothalamic-pituitary portal system?
links two capillary beds for an exchange between blood and tissue to occur
- What is controlled by hypothalamic tropic hormones?
- Neural input (cortex and limbic system)
- Hormonal (released in bloodstream to circulate through body and return back to brain)
- negative feedback - Circadian Rhythm (suprachiasmatic nucleus of the hypothalamus)
- master time keeper for whole body
- What is the function of the pineal gland?
Secretes melatonin
- plays an important role in the timing of seasonal processes in mammals
- What are the three primary endocrine organs?
- pituitary gland
- pancreas
- gonad
- What are the hormones of the thyroid gland?
- Thyroid Hormone T4 - regulate metabolism
- Thyroid Hormone T3 - regulate metabolism
- Calcitonin - regulates calcium levels in the body
- What is secreted by the thymus and what is its function?
secretes thymosin
- regulates T cell function to fight disease
- What hormone is secreted by the zona glomerulosa of the adrenal gland? and what does it do?
mineralocorticoids (aldosterone)
- regulates sodium and potassium levels
- stimulates sodium reabsorption and potassium secretion by the kidney tubules
- What zone are glucocorticoids (cortisol) released from in the adrenal glands? and what does it do?
secreted from zona fasciculata and zona reticularis
- regulates body’s response to stress and metabolism
- What zone are sex hormones (androgens) released from in the adrenal glands? and what do they do?
secreted from zona fasciculata and zona reticularis
- regulate reproductive function
- What does the adrenal medulla release?
releases adrenaline
- What do alpha cells secrete? and what is its function?
glucagon - raise blood glucose levels; mobilizes energy by promoting glycogenolysis and gluconeogenesis
- What do beta cells secrete? and what is its function?
insulin - lowers blood glucose levels; store energy by promoting protein, triglyceride, and glycogen synthesis
- What do delta cells secrete? and what is its function?
somatostatin - inhibits secretion of pancreatic hormones; regulates digestion and absorption of nutrients by the gastrointestinal system
- What do exocrine cells of the pancreas secrete? and what are their functions?
acinar cells and duct cells - secrete fluid and enzymes
- secretions enter the digestive tract via the pancreatic duct
- What do f cells secrete? and what are their functions?
pancreatic polypeptide -
- What are the secondary endocrine organs?
- heart
- kidneys
- GI tract
- liver
- skin and kidneys
- fat
- What are the 3 ways in which hormone levels in the blood are controlled?
- rate of hormone secretion
- amount of hormone bound to plasma proteins
- rate of hormone metabolism
*NOT FEEDBACK LOOPS
- How are hydrophilic hormones transported?
This would include peptides and catecholamines
- they are dissolved in plasma
- How are hydrophobic hormones transported?
Steroids and thyroid hormones
- They are bound to carrier proteins
- only free hormones can bind to receptors and be metabolized
- binding to carrier proteins gives them longer half-life
- Where are the sites of hormone metabolism?
- Target cell
- blood
- liver
- Where can lipophilic hormones be stored?
in adipose tissue
- What is an antagonism hormone interaction?
effects of hormone oppose each other
i.e glucagon vs. insulin
- What is an additive effect hormone interaction?
net effect equals the sum of the individual effects
- What is a synergism hormone interaction?
effects of two hormones favor each other but the net effect exceeds the sum of individual effects
i.e the effects of glucagon, cortisol, and epinephrine on blood glucose
- What is a permissiveness hormone interaction?
one hormone is needed for another to exert its effects
i.e estrogen causes expression of progesterone receptors in the uterus
- What is the function of prolactin? What are its hypothalamic precursor hormones?
- stimulates development of the breasts and milk secretion by the mammary glands
- Pituitary releasing hormone (+) and pituitary inhibiting hormone (-)
- What is the function of thyroid stimulating hormone? What is its hypothalamic precursor hormone?
- stimulates secretion of thyroid hormones by the thyroid gland
- thyroid releasing hormone
- What is the function of adrenocorticotropic hormone? What is its hypothalamic precursor hormone?
- stimulates glucocorticoid secretion by the adrenal cortex
- corticotropin releasing hormone
- What is the function of growth hormone? What are its hypothalamic precursor hormones?
- essential for growth; stimulates bone and soft-tissue growth; regulates protein, lipid, and carbohydrate metabolism
- GH releasing hormone and GH inhibiting hormone
- What is the function of luteinizing hormone and follicle stimulating hormone? What are its hypothalamic precursor hormone?
follicle stimulating hormone: in females. stimulates growth and development of the ovarian follicles, estrogen secretion
in males, stimulates sperm production by the testis
luteinizing hormone: in females, stimulates ovulation, transformation of the ovarian follicle into the corpus luteum, and secretion of estrogen and progesterone
in males, stimulates testosterone secretion by the testis
- gonadotropin releasing hormone
