MC A&P final with sensory & endocrine

Question Answer
sclera s: dense fibrous CT "white" part of eye
f: stabilizes shape of eye during movement by muscles
cornea s: transparent area anterior surface of eye composed of dense matrix of multiple collagen fiber layers
f: permits passage of light & curvature aids focusing process
choroid s: cascular layer covered by sclera
f: capillary network delivers 02 & nutrients to tissue within neural tunic
ciliary body s: thickened region bulges into interior its ligaments extend to lens
f: supports the lens & controls its shape behind the pupil
iris s: colored part contains blood vessels, pigament cells, & layers of smooth muscle fibers
f: changes the diameter of the pupil with muscle fibers
retina outer pigmented layer contains photo-receptors
inner nervous tissue layer contains supporting cells & neurons that perform preliminary processing & integration of visual info
photoreceptors rod: allows to see in dimly lit but can't discriminate color
cones: give color & sharper images required in intense light
optic disc s: where the optic nerve comes in
why? no retina can attach to the spot
fovea centralis site of sharpest vision where we want light to go
3 chambers & area place: between
anterior: cornea & iris
posterior: iris & lens
vitreous: behind lens
aqueous humor location: anterior cavity
f: provides transportation for nutrient & waste, forms a fluid cushion, helps retain eye shape, stabilizes position of retinal
vitreous humor location posterior cavity
glaucoma build up of fluid in the eyes because no blood can flow->no O2->effects retina->eventually lose photoreceptors
lens held behind the iris by suspensory ligaments
composed of lens fibers surrounded by a capsule
focuses light on the retina
bulges for near vision & no tension
flattens for distant & has tensiion
cataract lens becomes clouded & can happen with general age
eyelids levator palpebrae superioris & orbiculari oculi
tarsal glands
conjunctiva protect doesn't allow things to go back in eye
layers: palpebral (inner of eyelid) & bulbar
conjunctivitis pink eye
lacrimal apparatus glands: produces tears & enzyme lysozyme & antibodies for antibacterial
lacrimal papilla
punctum
lacrimal canal
lacrimal sac
nasolacrimal duct
extrinsic muscles lateral rectus- laterally
medial rectus- medially
superior rectus- up & in
inferior rectus- down & in
superior oblique- down & out
inferior oblique- up & out
5 processes required for focusing of light waves & stimulation of photoreceptors 1. light waves in
2. refraction through media
3. accomodation of lens
4. constriction of pupil regulate light into vitreous
5. convergence of eyeballs=acuity
transmission of light waves cornea -> aqueous humor -> lens -> vitreous humor
refraction bending of light waves occurs when light passes @ an angle of one density to another
light focuses on the retina upside down & reversed L to R brain fixes
structures in refraction & why cornea- major bender
fluids very little effect
lens- adjust the shape of your lens to sharpen images by getting them to cross @ fovea ciliary body & smooth muscle adjusters
lenses convex- converge light waves
concave- diverge light adjust it
myopia "nearsighted" crosses too far away from retina b/c bend too soon could be lens
hyperopia "farsighted" light waves don't bend very much & don't cross b4 fovea
accomodation automatic adjustment of the curvature of the lens by contraction of the ciliary muscles to focus light waves on retina
occurs when objects are viewed closer than 20 ft
how lens bulges ciliary muscles contract & suspensory ligaments are loosened & lens bulges for accomodation
presbyopia accomodation disorder lens loses elasticity & near images focus behind retina old age "nearsight"
constriction of pupil radial- contract bigger/dilate
circular- contract smaller/constrict
triggered by light intensity & near vision
pathways:
~ parasympathetic of circular
~ sympathetic to radial dilate pupil
convergence of the eyeballs eyes rotate medially when viewing close objects with medial rectus
light waves entering each eye will focus on the same part of retina
amblyopia lazy eye
deviation of one eye
no concurrent convergence
2 images perceived by visual cortex
retinal pigaments composed by Vitamin A:orange & red veggies
stimulation of photo receptors photon of light reaches rod pigaments absorbs the light -> retinal & opsin separate from each other -> retinal is converted to original shape with use of ATP -> retinal & opsin comes back together nothing can happen in cell while doing this
achromatopsia color blindness missing certain pigments in cones
nyctalopia night blindness something wrong with the rods usually caused by prolonged deficiency of vitamin A which can permanently damage
pathway of vision to brain photoreceptors -> neurons of retina -> optic nerve -> optic chiasma -> optic tract -> thalmus -> primary visual cortex occipital lobe
binocular vision & depth perception field of vision overlaps
when only one eye functions properly depth perception is lost
blindness from same eye
so left field = left eye blind
auricle is composed of elastic cartilage
skin
helix
lobe
tragus
external auditory canal where ceruminous glands are
tympanic membrane double layer epithelium that can repair self
sensory innervation by cranial nerves
middle ear air-filled chamber=tympanic cavity
seperated from outer by eardrum inner by round & oval windows
eustachian tube that adjust pressure to equalize pressure on both sides of tympanic membrane
ossicles malleus, incus, & stapes
transmit sound waves from tympanic membrane to oval window
muscles in ear tensor tympani attaches to malleus
stapedius attaches to stapes
involved in reflexes to prevent damage to membranes & receptors
inner ear acts like bicycle tire
bony labyrinth contains fluid known as perilymph outer tube
membranous labyrinth contains endolymph inner tube
vestibule, semicircular canals, cochlea, organ of corti
vestibule bony contains round & oval windows
membranous 1. utricle top & saccule little 2. macula contains hair cells which sense gravity & linear movement & change in position of head
otoliths rocks in ear that moves with gravity on top of gel of cilia from macula static
semicircular canals membranous- semicircular ducts
ampulla- swellings where ducts connect with utricle
crista ampullaris contains hair cells which sense dynamic rapid turns embedded in flat gel called the capula
cochlea chambers: scala vestibuli- upper & continuous with vestibule & scala tympani- lower ends at round window both contain perilymph
cochlear duct – middle with endolymph roof: vestibular membrane & floor: basilar membrane
organ of corti in coclear duct along basilar membrane
where mechanical impulses converted to nerve impulse
sensory cells are hair cells 16,000 embeded on tectorial membrane
functional unit of hearing
otitis media middle ear infection usually bacterial some viral
tubes put in the membrane to drain fluid
conduction deafness conduction pathway usually b.w tympanic membrane to the oval window sometimes even the fluids or b4 the membrane are effected
causes: earwax, infection of middle ear, stuff in ear
sensory deafness something wrong with the receptors cells, craniall nerve VIII temporal lobe anything starting at the receptors to where the perception occurs
tinnitus "ringing in your ears" irritated cells by over stimulation like driving in car for long time
smell location: roof of nasal cavity
receptors: chemoreceptors-smell dissolves & can note smell & stimulated by chemicals dissovled in fluids (breathe in gas_
olfactory organs found in the roof of the nasal cavity
composed of olfactory receptor cells (bipolar neurons with cilia) surrounded by supporting epithelial cells
olfactory pathway olfactory receptor cells -> through the holes in the ethmoid bone to the olfactory bulb -> olfactory tracts -> medial temporal lobe
lesions in olfactory hallucination usually bad smell

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