endocrine upload Flashcards
(103 cards)
Endocrine gland
secrete hormones into the bloodstream from the interstitial fluid. Then, acts on cells (target cells).
Exocrine gland
enter tubes or ducts that lead to body surfaces. EX: stomach acid reaching the lumen of the digestive tract; sweat released at the skin_s surface.
5 chemical classes of hormones: amines
formed from amino acids _ examples: norepinephrine, epinephrine.
5 chemical classes of hormones: peptides
formed from amino acids _ examples: ADH, OT, TRH, SS, GnRH
5 chemical classes of hormones: proteins
formed from amino acids _ examples: PTH, GH, PRL
5 chemical classes of hormones: glycoproteins
formed from protein & carbs _ examples: FSH, LH, TSH
5 chemical classes of hormones: steroids
formed from cholesterol _ examples _ estrogens, testosterone, aldosterone, cortisol.
Sequence of steroid hormone
_ Endocrine gland secretes steroid hormone.
_ Steroid hormone diffuses through target cell membrane & enters cytoplasm or nucleus.
_ Hormone combines w/ receptor molecule in cytoplasm or nucleus.
_ Steroid hormone-receptor complex binds to DNA & promotes transcription of messenger RNA.
_ Messenger RNA enters cytoplasm and directs protein synthesis.
_ Newly synthesized proteins produce hormone_s specific effects.
Sequence of nonsteroid hormone
_ Endocrine gland secretes nonsteroid hormone.
_ Body fluid carries hormone to its target cell.
_ Hormone combines w/ receptor site on membrane of its target cell, activating G protein.
_ Adenylate cyclase molecules are activated in target cell_s membrane.
_ Adenylate cyclize circulates ATP into cyclic AMP.
_ Cyclic AMP activates protein kinases.
_ Protein kinases activate protein substrates in the cell that change metabolic processes.
_ Cellular changes produce the hormone_s effects.
Control of hormonal secretions by negative feedback
o Hypothalamus controls the anterior pituitary gland_s release of tropic hormones, which stimulate other endocrine glands to release hormones. Hypothalamus constantly receives information about the internal environment from neural connections about the internal environment from neural connections & cerebrospinal fluid, made possible by its location near the thalamus and the third ventricle.
o Nervous system directly stimulates some glands. Adrenal medulla secrets its hormones (epinephrine & norepinephrine) in response to preganglionic sympathetic nerve impulses. Secretory cells replace postgang sympathetic neurons, which would normally secrete norepinephrine alone as a transmitter.
o A change in the composition of the internal environment is another source to which another group of hormones directly response. Ex: when blood glucose level rises, the pancreas secretes insulin, and when the blood glucose level falls, it secretes glucagon.
Identify and locate adenohypophysis (anterior pituitary)
looks like a pair of balls, this one is in the front
Identify and locate adrenal cortex
makes up bulk of the adrenal gland, 3 layers- zona glomerulosa, faciculata, reticularis. Adrenal medulla is inside
Identify and locate adrenal gland
shaped like pyramids - consists of cortex & medulla, on top of kidney
Identify and locate adrenal medulla
inner part of adrenal gland
Identify and locate follicle-thyroid
capsule of connective tissue covering the thyroid gland, secretes hormones that may be stored inside the thyroid gland (colloid) or released into nearby capillaries.
Identify and locate hypophysis
aka pituitary gland
Identify and locate infundibulum
atttaches the pituitary gland to the hypothalamus (stalk)
Identify and locate islets of langerhans
clusters inside pancreas which secrete hormones
Identify and locate neurohypophysis (posterior pituitary)
looks like a pair of balls, this one is in the back
Identify and locate ovary
little balls attached to fallopian tubes
Identify and locate pancreas
next to small intestine, looks like a comma
Identify and locate parathyroid gland
little beans on the thyroid gland
Identify and locate pituitary gland
the balls, made up of the adenohypophysis (front ball) and the neurohypohysis (back ball)
Identify and locate pineal gland
near roof of 3rd ventricle, in the brain