Z 342 lab final Flashcards
outer and middle ear function in
hearing only
inner ear function in
hearing and equilibrium
auricle/pinna
elastic cartilage; funnels sound waves into external auditroy meatus; helix = rim; lobule = earlobe
external auditory meatus
transmits sound to eardrum; temporal bone
tympanic membrane
eardrum; connective tissue, vibrates and transfers sound energy to tiny bones of middle ear
middle ear
tympanic cavity; small air-filled musosa lined cavity in temporal bone; malleus, incus, stapesl; opening to auditory tube
inner ear
bony labyrinth: perylymph; 3 regions: vestibule, semicircular canals, cochlea; membranous labyrinth: endolymph
vestibulo….
balance
cochlear
hearing
physiology of hearing
- sounds waves vibrate tympanic membrane 2. auditory ossicles vibrat, pressure amplified 3. pressure waves by stapes push on oval window, move through fluuid in scala vestibuli 4. sounds with frequencies below hearing level do not excite har cells 5. sounds in hearing range go through cochlear duct, vicration basilar membrane and deflecting hairs on inner hair cells
auditory pathway
ascending; auditory info from cochlear receptors (inner hair cells) to cerebral cortex
vestibular apparatus
sends signals to brain that initiate reflexes needed to make changes in position
vestibule
sense of static equilibrium (gravity) - key role in maintaining posture; maculae in vestibule wall
semicircular canals
sense of dynamic equilibrium (rotation), receptors for rotational head movement; cristae at base of each canal
maculae hair cells
monitor position of head in space, key role in controlling posture
otoliths
ear stones increase membrane’s weigth over hair cells and resistance to changes in motion; hairs verticle when head upright; hair cells synapse with fibers of vestibular nerve
cristae hair cells
cristae is receptor for roational acceleration in semicircular canals; rotational movement - endolympth moves capula in opposite direction
differences between nervous and endocrine
endocrine: slower, long term effects, affect target cells (specific or most of body)
similarites between nervous and endocrine
communication and coordination of responses, some organs shared, stimulated by sensory input by neurons, hypothalamic control of both (endocrine and autonomic NS)
exocrine glands
produce non hormonal substances
endocrine glands
produce hormones (single or many), variable stimuli elicit hormone secretion
master regulator of endocrine system
hypothalamus
9 pituitary hormones
ACTH, TSH, GH, PRL, FSH, LH, MSH, ADH
posterior pituitary hormones
oxytocin and ADH
amino acid based hormones
water soluble, free in blood, acts on cell membrane receptors, shorter half life
steroid based hormones
fat soluble, via carrier proteins in blood, acts on receptors inside cell, longer half life, snythesized from choleserol, only gonadal and adrenocortical hormone are steroids
humoral stimulus
ion concentration in blood
neural stimulus
stress, preganglionic, sypathetic nerve fibers
hormonal stimulus
hormones secreted by hypothalamus
negative feedback
production of end product inhibits production of intermediary product
permissiveness
hormone needs another to have full effect
synergism
effects of presence of 2 hormones together is amplified
antagonism
one hormone opposes the action of another
TRH
thyrotropin releasing hormone; produced and released by hypothalamus, target cells: anterior pituitary that release TSH
TSH
thyroid stimulation hormone; produced and released by anterior pituitary, target cells: cells of thyrid gland
TH
thyroid hormone (T3 or T4); produced and released by thyroid, target cells: al cells of body, metabolic rate of body
GnRH
gonadotropin releasing hormone; produced and released by hypothalamus; target cells: anterior pituitary that produce FSH adn LH
GH
growth hormone; produced and released by anterior pituitary; target cells: all cells of body
GHRH
growth hormone releasing hormone; produced and secreted by hypothalamus; target cells: cells of anterior pituitary that make GH
GHIH
growth hormone inhibiting hormone, somatostatin; produced and released by hypothalamus; target cells: anterior pituitary that mke GH
IGFs
insulin like growth factors, somatomedians; produced and released by liver; target cells: all cells of body
PTH
paraythroid hormone; produced and released by parathyroid glands; target cells: bone, GI tract, kidney
calcitonin
produced and released by thyroid gland; target cells: bone, GI tract, kidney
glucagon
produced and released by pancreas; target cells: muscle, liver, fat
insulin
produced and released by pancreas; target cells: all cells except neural
FSH
follicle stimulating hormone; produced and released by pituitary; target cells: gonads (sustentacular cells of male, follicle cells of femal)
LH
lutenizing hormone; produced and released by anterior pitutiary; target cells: gonads (interstitial leydig cells in male, follicle cells and eggs of female)
testosterone
produced and released by leydig (interstitial) cells of testes; target cells: all cells of body, sustentacular (sertoli) cells
estrogen
produced and released by follicle cells of ovaries, placenta; target cells: all cells, uterus, ovary
inhibin
produced and released by cells of testes and ovary; target cells: hypothalamus, anterior pituitary that make FSH
progesterone
produced and released by follicle cells of ovary (corpus luteum); target cells: uterus, breasts
CRH
corticotropin releasing factor; produced and released by hypothalamus; target cells: anterior pituitary that make ACTH
ACTH
adrenocorticotropic hormone; produced and released by anterior pituitary; target cells: adrenal cortex
epinephrine/norepinephrine
produced and released by adrenal medulla; target cells: all cells of body
glucocorticoids
cortisol, corticosterone, etc; produced and released by adrenal cortex; target cells: liver, all body cells
steriod hormones are synthesized from
cholesterol
seminal vesicles
enhance sperm motility and fertility; yellow, viscous alkaline fluid w/fructose, ascorbic acid, coagulate, and prostaglandins, 70% of volume
prostate gland
activates sperm; milky, slightly acidid, citrate, enzymes, 30% of semen
bulbourethral gland
neutralizes traces of acidic urine in urethra, thick, clear mucus
path of sperm
testes, epididymis, vas deferens, seminal vesicle, prostate gland, penis
semen + sperm
10% sperm, 20-150 million sperm, pH 7.3-7.7
estrogen released by
follicel cells
progesterone released by
corupus luteum
fibrous tunic
cornea and sclera
sclera
white of eye
cornea
outer covering, light bending
pupil constricts as circular muscles
contract
pupil dilated as radial muscles
contract (circular muscles relax)
superior oblique
move eye down and laterally; trochlear (IV)
inferior oblique
move eye up and laterally; oculomotor (III)
lateral rectus
abducens (VI)
superior rectus, inferior rectus, medial rectus, inferior oblique
oculomotor (III)
3 tunics of eye
fibrous = sclera and cornea; vascular = choroid, ciliary body, iris; neural = 2 layered retina
crystalins
proteins that make up lens
accommodation
change in lens shape to focus on near object ; when ciliary muscle relaxes, suspensory ligaments stretch on lens which flattens it; when ciliary muscle contracts there is less pressure to stretch so lens is fat
optic chiasm
where sides cross in visual pathway