endocrine and the ear
Card Set Information
endocrine and the ear
endocrine maria hutchins
test in the ear and endocrine
What are the three parts of the ear?
external outer ear
middle ear (tampanic cavity)
internal (inner) ear
what 2 sections of the ear are involved with just hearing?
external and middle
which part of the ear functions not only for hearing but also for balance?
what are the parts of the external ear?
external acoustic meatus
the auricle of the external ear is made of what two parts?
what are the 3 functions of the tympanic membrane
boundry between external and middle ear
connective tissue membrane that vibrates in response to sound
transfers sound energy to the bones of the middle ear
what is the middle ear
small air filled mucosa lined cavity in the temporal bone
the middle ear is flanked laterally by what ?
what connects the middle ear to the nasopharynx?
the pharyngotympanic or eustachian or auditory tube
what is the function of the pharyngotympanic tube?
equalize pressure in the middle ear cavity with the external air pressure
what are the 3 small bones in the tympanic cavity
malleus, incus, and stapes
what is the function of the ear ossicles (3 bones)
transmits vibratory motion of the eardrum
what are the 2 labryrinth of the internal ear
where are the labyrinth of the internal ear?
what are the three parts of the bony labyrinth
the bony labyrinth is filled with a sodium rich substance called
what are the membranous labyrinth
series of sacs within the bony labyrinth
what potassium rich substance fills the membranous membrane
what are the vestibular receptors called
what are the semicircular receptors
what does the vestibular apparatus consist of
equilibrium receptors in the semicircular canals and vestibule
what does the vestibular receptors monitor
what does the semicircular canal receptors monitor
what is the vestibule
central egg shaped cavity of the bony labyrinth
the vestible contains 2 membrenous sacs what are they?
the saccule is continuous with what
the utricle is continuous with what?
what is the functions of the saccule and the utricle?
house equilibrium receptor regions (maculae)
respond to gravity and changes in the position of the head
maculae are the sensory receptors for what type of equilibrium?
what are the functions of maculae?
monitor the position of the head in space necessary for the control of posture
maculae in the utricle respond to what type of movement of the head; horizontal side to side or verticle?
horizontal side to side
maculae in the saccule respond to what type of movement of the head; horizontal side to side or verticle?
what are the 3 canals that make up the semicircular canals?
what lines the canals and what does it communicate with?
membranous semicircular ducts line the canals and communicate with the utricle
the ampulla of each canal of the semicircular canals house an equilibrium receptor region called
the crista ampullaris
the cristae ampullaris responds to what type of movements of the head?
from what does the cochlea extend?
what does the cochlear duct house?
body of corti
the cavity of the cochlea is divided into how many chambers?
the cochlear branch of nerve VIII runs from where to where?
the organ of corti to the brain
the endocrine system influences metabolic activities by what means?
hormones transported in the blood
how do responses to the endocrine system compare to those of the nervous system
the responses are slower but last longer
what are 5 endocrine glands
the hypothalamus has another function other than just endocrine what is it
what are some other tissues and organs that produce hormones? (5)
cells in the walls of the small intestine
what are the chemical messengers that carry long distance chemical signals that travel in blood and in lymph?
hormones have two classifications they are?
what is steroid hormones structurally related to?
are steroid hormones lipid soluble
what 3 glands secrete steroid hormones?
nonsteroid hormones are structurally related to what?
are non-steroid hormones lipid soluble?
what five things secrete non-steroid hormones?
do steroid or non-steroid hormones enter cells?
do steroid or non-steroid hormones activate specific genes to produce specific protiens?
do steroid or non-steroid hormones bind to receptors on as target cell membranes?
are steroid or non-steroid hormones water soluble?
are steroid or non-steroid hormones lipid soluble?
do steroid or non-steroid hormones work through intermediate mechanisms to activate existing enzymes?
do steroid or non-steroid hormones have the fastest action?
Where are adrenocorticotropic receptors only found?
certain cells of the adrenal cortex
thyroxin receptors are found where ?
nearly all the cells of the body
what 3 factors does target cell activation depend on?
blood levels of the hormone
relative number of receptors on or in the target cell
affinity of binding between receptor and hormone
hormones circulate through the blood in one of two states what are they?
free or bound
what are the 2 hormones that need carriers?
steroid and thyroid hormones need a carrier all other hormones circulate without carriers what is the carrier used?
the concentration of a circulating hormone reflects what ?
rate of release
speed of inactivation and removal from the body
hormones are removed from the blood by what 4 things
: the time required for a hormones blood level to decrease by half
what are the two ways multiple hormones may act?
what occurs in hormone synergism?
more than one hormone produces the same effect on a target cell
what occurs in hormone antagonism
one or more hormones opposes the action of another hormone
blood levels of hormones controled by?
negative feedback system
how do blood levels of hormones vary?
only within a narrow desireable range
hormones are synthisized and released in response to what 3 things?
how does a humoral stimuli stimulate secretion of hormones?
by changing blood levels of ions and nutrients
nerve fibers stimulate hormonal release
how does hormonal stimuli stimulate hormone release?
hormones stimulate other endocrine glands to relesase thier hormones
what is nervous system modulation?
the nervous system modifies the stimulation of endocrine glands and thier negative feedback mechanisms
what are the 2 lobes of the pituitary?
posterior / neurohypophysis
what does the hypophyseal portal system carry?
releasing and inhibiting hormones to the anterior pituitary to regulate hormone secretion
what are the 6 anterior pituitary hormones and thier abbreviations?
growth hormone (GH)
thyroid stimulating hormone (TSH) or thyrotropin
adrenocorticotropic hormone (ACTH)
follicle stimulating hormone (FSH)
lutienizing hormone (LH)
anterior pituitary hormones are all protiens
True or False?
what 4 out of the 6 anterior pituitary hormones are tropic?
if a hormone is tropic what does it do?
stimulate the secretion of other endocrine glands
Growthn hormone stimulates most cells but what are its 2 targets
thyroid stimulating hormone stimulates what?
normal development and secretory activity of the thyroid
Adrenocorticotropic hormone (corticotropin) stimulates what?
the adrenal cortex to relesase corticosteroids
what 2 hormones are gonadotropins?
follicle stimulating hormone
FSH stimulates what?
gamete (egg or sperm) production
LH stimulates or promotes what?
production of gonadal hormones (absent in prebudecents)
What does Prolactin stimulate?
what does the posterior pituitary contain?
axons of hypothalmic neurons
what does the posterior pituitary store (2)
Antidiuretic hormone (ADH) and oxytocin
the posterior pituitary releases stored ADH and oxytocin in response to what?
what are the functions of oxytocin? (3)
stimulates uterine contractions
triggers milk ejection
plays a role in the sexual arrousal and orgasm in males and females
what are the functions of the antidiuretic hormone?
increases water retention
what substance can inhibit the release of ADH and cause excess urine output?
Thyroid gland consists what?
2 lateral lobes connected by a median mass
what is the median mass in the thyroid gland called?
thyroid gland prioduces what hormones?
Thyroid Hormone (TH) consists of two related compounds what are they?
T4 thyoxine how many thyrosine molecules and how many iodine atoms?
2 thyrosine molecules
4 bound iodine atoms
T3 triiodothyronine contains how many thyrosisne molecules and how many iodine atoms?
3 bound iodine atoms
thyroid hormone is also know as the major ____ hormone
thyroid hormone increases _____ _____ and ____ production.
what is the negative feedback regulation of thyroid hormone release?
rising levels of TH provide negative feedback inhibition on the release of TSH
calcitonin is an antagonist to what hormone?
parathyroid hormone PTH
what is the most important hormone in calcium homeostasis?
parathyroid hormone PTH
does PTH increase or decrease Ca2 levels
what is the negative feedback control of Parathyroid glands?
rising Ca2 inhibits PTH release
what are adrenal (suprarenal) glands?
Paired pyramid shaped organs atop the kidneys
structurally and funtionaly the adrenal suprarenal glands are two glands in one what are the 2 parts?
the adrenal medulla is made of what type of tissue?
the adrenal medulla is part of the sympathetic or parasympathetic nervous system?
the adrenal cortex is made of three layers of what type of tissue?
the adrenal cortex synthisize and release what ?
what are the 3 layers of the adrenal cortex?
zona glomerulosa produces what corticosteroid?
what corticosteroid does the zona fasciculata produce?
what corticosteroid does the zona reticularis produce?
sex hormones or gonadocorticoids
what do mineralcorticoids regulate?
electrolytes in ECF
what is the most important mineralcorticoid?
aldosterone stimulates what?
sodium reabsorbtionand water retention by the kidneys
glucocorticoids keep what levels constant?
how do glucocorticoids maintain blood pressure?
by increasing the action of vasoconstrictors
glucocorticoids supress what type of responces
what is the most significant glucocorticoid?
cortisol is released in response to what hormone?
what else could trigger the release of cortisol?
eating patterns and activity, stress
what is the prime metabolic effect of cortisol?
gluconeogenisis is the formation of glucose from what?
fat and protiens
cortisol promotes rises in what 3 things?
most gonadocorticoids are what?
androgens that are converted to testosterone in tissue cells
(estrogen in females)
what does the adrenal medulla secrete? (2)
epinephrine and norepinephrine
epinephrine and norepinephrine cause what (4)
blood glucose to rise
blood vessles to constrict
the heart to beat faster
blood to be diverted to the brain, heart, and skeletal muscle
epinephrine stimulates what (3)
bloodflow to skleletal mauscles and heart
what does norepinephrine influence?
peripheral vasoconsrtiction and blood pressure
what is the pineal gland?
samll gland hanging from the roof of the third ventricle
pineal gland secretes what?
melatonin may affect what? (3)
timing of sexual maturation
psysiological processes that show the rythmic variations (body temp, sleep, appitite)
what is the shape and location of the pancreas?
trangular shaped behind the stomach
the pancreas has what 2 types of cells
what are the exocrine cells of the pancreas
what does the acinar cells of the pancreas do?
produce an enzyme rich juice for digestion
what contains the endocrine cells in the pancreas?
pancreatic islets (islets of langerhans)
what are the 2 endocrine cells located in the pacreatic islets ?
what does alpha cells produce
glucogon (hyperglycemic hormone)
what does the beta cells produce?
insulin (hypoglycemic hormone)
what is the major target of glucogon?
what does glucogon promote in the liver?
release of glucose to the blood
what occurs in glycogenolysis?
break down of glycogen to glucose
what occurs in gluconeogenesis?
synthesis of glucose from lactic acid and noncarbohydrates
glucogon is synergistic with what (both raise blood glucose)
what are the 4 effects of insulin?
lowers blood glucose levels
enhances membrane transport of glucose into fat and muscle cells
participates in neural development and learning and memory
inhibits glycogenolysis and gluconeogenesis
what condition causes an imbalance of insulin?
what are the three signs of diebetes mellitis?
polyuria - huge output of urine
polydipsia - excessive thirst
polyphagia - excessive hunger
what are "other" hormone producing structures?(5)
what hormone does the heart produce?
atrial natriuretic peptide (ANP) (also known as atrial natriuretic hormone (ANH))
kidneys produce what hormones?
erythropoietin - production of RBC's
Renin - renin-agiotensin mechenism
thymosine is involved in the normal development of what?
T lymphocytes in the immune response