Lesson 1 - Eyes and Ears Flashcards
eyelid aka
palpebrae
what do eyelids do?
cover the eyes
medial/lateral commissure (canthus)
median and lateral junctions of upper and lower eyelids
lacrimal caruncle
located on the medial commissure, produces oily secretions
conjunctiva
inner surface of the eyelid, secretes mucus
lacrimal apparatus
secretes tears that contain lysozyme
the lacrimal apparatus consists of (4)
- lacrimal gland
- lacrimal canaliculus
- lacrimal sac
- nasolacrimal duct
ciliary glands
modified sweat glands found between eyelashes, lubricates the eye
tarsal glands
sebaceous glands posterior to the eyelashes, produces oily secretion, lubricates eye
six extrinsic eye muscles
- lateral/external rectus
- medial/internal rectus
- superior rectus
- inferior rectus
- inferior oblique
- superior oblique
lateral rectus: action
moves eye laterally
lateral rectus: controlling cranial nerve
not III oculomotor
VI (abducens)
medial rectus: action
moves eye medially
medial rectus: controlling cranial nerve
III oculomotor
superior rectus: action
elevates eye and turns it medially
superior rectus: controlling cranial nerve
III oculomotor
inferior rectus: action
depresses eye and turns it medially
inferior rectus: controlling cranial nerve
III oculomotor
inferior oblique: action
elevates eye and turns it laterally
inferior oblique: controlling cranial nerve
III oculomotor
superior oblique: action
depresses eye and turns it laterally
superior oblique: controlling cranial nerve (not III)
IV trochlear
three layers of the eye
- fibrous layer
- vascular layer (uvea)
- sensory layer
eye fibrous layer
outer connective tissue layer consisting of the sclera and cornea
sclera
white of the eye
cornea
transparent anterior structure for light entry
eye vascular layer (uvea)
what layer of the eye? what is the most anteiror part?
middle layer of the eye; the iris is the most anterior part
ciliary body (2)
found anteriorly; composed of ciliary muscles to control lens shape and ciliary processes to secrete aqueous humor
choroid
found posteriorly; blood-rich nutritive layer containing dark pigments preventing light scattering
eye sensory layer
innermost layer, contains the two layers retina
two layers of the retina
- pigmented epithelial layer
- neural (nervous) layer
retina pigmented epithelial layer
where is this located? what does it cover?
layer closest to the choroid layer; covers the ciliary body and posterior side of the iris
retina neural (nervous) layer
transparent layer containing photoreceptors (rod and cones); extends up to the ciliary body
rods
for black and white vision, used dim light
cones
for color vision, used in bright light
where are cones concentrated in the retina?
macula lutea
what is the center of the macula lutea called?
fovea centralis
where is your blind spot located?
at the optic disc where the optic nerves leave the eye
sensory ligament (ciliary zonule)
holds the lens vertically
what do ciliary muscle contractions change about the lens?
they change the thickness to focus light onto the retina
lens
found anteriorly, focuses light onto the retina
the lens divides the eye into two segments
anterior segment/cavity and posterior segment/cavity
anterior segment/cavity of the eye contains
contains watery aqueous humor
what is aqueous humor formed by?
ciliary bodies
what reabsorbs aqueous humor?
scleral venous sinus
posterior segment contains
contains gel-like vitreous humor
cells of the retinal layer: bipolar cells
connects and modulates input from photoreceptors to ganglion cells
cells of the retinal layer: ganglion cells
project axons to the brain via optic nerve and tract
where do ganglionic cell axons leave the eye?
optic disc
light stimulus causes impulses to travel from: (5)
- the optic nerves
- optic chiasma
- optic tracts
- superior colliculus and lateral geniculate body of the thalamus
- occipital lobe in the visual cortex
emmetropic eye
normal eye that focuses properly
myopia
near-sightedness; images focused in front of the retina
hyperopia
far-sightedness; images focused behind of the retina
prebyopia
far-sightedness caused by age-related decrease in lens elasticity
astigmatism
irregular corneal curvature that distort images
how to correct myopia
concave lens
how to correct hyperopia
convex lens
what causes myopia?
the eyeball being too long
what causes hyperopia?
the eyeball being too short
outer ear: auricle/pinna
composed of skin covered cartilage
external acoustic meatus
external auditory canal lined with ceruminous glands
ceruminous glands
secrete wax
tympanic membrane
eardrum that vibrates with same frequency as sound waves that enter canal
middle ear
consists of a tympanic cavity containing auditory ossicles
auditory ossicles (3)
- malleus
- incus
- stapes
the ossicles amplify and transmit tympanic membrane vibrations to the _____ _____
oval window on the cochlea
pharyngotympanic/auditory tube
connects the tympanic cavity to the nasopharynx and equalizes the middle ear pressure with outside air
internal ear
consists of a system of bony (osseous) labyrinth filled with aqueous fluid perilymph
inner ear: cochlea
involved in hearing
inner ear: vestibule
what is it involved in??
involved in equilibrium
inner ear: semicircular canals
involved in what process??
involved in equilibrium
perilymph
what is it? where is it found?
aqueous fluid in the inner ear
endolymph
aqueous lymph within the inner ear “bony labyrinth”
cochlear duct (scala media)
filled with endolymph, and separates cochlear cavity into upper chamber and lower chamber
scala vestibuli
upper chamber of the cochlear duct; terminates at the oval window with stapes, filled with perilymph
scala tympani
lower chamber of the cochlear duct; terminates at the round window; filled with perilymph
spiral organ
contains the sensory receptors
sensory receptors of the spiral organ
hair cells that project to the cochlear nerve and part of the vestibulocochlear nerve VIII
membranes of the spiral organ: basilar membrane
forms the floor of the cochlear duct where hair cells rest
membranes of the spiral organ: tectorial membrane
contains a gelatinous membrane that stereocilia from hair cells project into
membranes of the spiral organ: vestibular membrane
roof of the cochlear duct
how is sound converted to nerve impulses?
- The stapes send vibrations through the perilymph of the scala vestibuli and scala tympani
- these vibrations cause the basilar membrane to move and thus stimulate the air cells there
sensitivity to sound frequencies depends on the _____ of the hair cells
location
high frequency sounds are detected by…
primarily hair cells at the base of the cochlear duct
low frequency sounds are detected by…
primarily hair cells at the apex of the cochlear duct
Weber test
determines if sound conduction is equally loud for both ears
what might the Weber test indicate?
if the sounds are not equal in both ears, it may indicate sensorineural deafness from the side with less sound
Rinne test
compares conduction between bone and air
what does the Rinne test show you if air conduction sounds lower? (4)
can be caused by compared earwax, a perforated eardrum, inflammation of the middle ear, or damage to the ossicles
otitis media
inflammation of the middle ear
vestibular apparatus
suspended in?
composed of?
suspended in perilymph; is composed of the
- utricle
- saccule
vestibular apparatus: urticle
detects horizontal acceleration
vestibular apparatus: saccule
detects vertical acceleration
semicircular canals
contain?
contains the membranous semicircular ducts
semicircular ducts
monitor what?
monitors angular acceleration (dynamic equilibrium)
three semicircular ducts
what are they called?
anterior, posterior, and lateral
vestibule and semicircular canals are filled with _____
endolymph
vestibule: the utricle and saccule contain hair cells that project _____ and _____
stereocilia and kinocilium
vestibule: where do stereocilia and kinocilium project?
into the otolithic membrane
vestibule: otolithic membrane
gelatinous material containing calcium carbonate crystals called otolith
otolith
calcium carbonate crystals in the vestibule
what does movement of the head cause?
the otolithic membrane to move and stimulate or inhibit the hair cells to alter electrical signals sent along the vestibular nerve to the brain
semicircular canals contain
contain hair cells in the crista ampullaris or the ampulla
ampullary cupula
a gelatinous cap covering the crista ampullaris
Label A-D
A: palpebral conjunctiva
B: tarsal glands
C: cornea
D: bulbar conjunctiva
Label A-C
A: lacrimal sac
B: medial commissure
C: lacrimal caruncle
Label D-F
D: lacrimal gland
E: excretory ducts of lacrimal glands
F: lateral commissure
Label G-I
G: lacrimal punctum
H: lacrimal canaliculus
I: nasolacrimal duct
Label A-C
A: optic nerve
B: inferior rectus muscle
C: inferior oblique muscle
Label D-G
D: lateral rectus muscle
E: superior rectus muscle
F: superior oblique tendon
G: superior oblique muscle
Label A-C
A: superior oblique muscle
B: superior oblique tendon
C: superior rectus muscle
Label D-G
D: optic nerve
E: lateral rectus muscle
F: medial rectus muscle
G: inferior rectus muscle
Label A-C
A: ciliary body
B: ciliary zonule
C: cornea
Label D-F
D: iris
E: pupil
F: ciliary zone
Label G and H
G: sclera
H: choroid
Label A-C
A: ciliary processes
B: iris
C: cornea
Label D and E
D: choroid
E: sclera
Label A-D
A: ciliary body
B: ciliary processes
C: choroid
D: sclera
Label A-C
A: iris
B: pupil
C: retina
Label D-G
D: macula lutea
E: fovea centralis
F: optic nerve
G: optic disc/blind spot
Label A-C
A: iris
B: retina
C: fovea centralis
Label D-F
D: optic nerve
E: optic disc
F: retina
Label A-D
A: anterior chamber of anterior segment (has aqueous humor)
B: lens
C: scleral venous sinus
D: posterior segment (contains vitreous humor)
Label A-C
A: anterior segment
B: lens
C: ciliary zonule (suspensory ligament)
Label E-G
F is not the iris
E: vitreous humor in posterior segment
F: lens (posterior aspect)
G: ciliary zonule (suspensory ligament)
Label A-C
A: axons of ganglion cells
B: ganglion cells
C: bipolar cells
Label D-F
D: photoreceptors
E: rods
F: cone
Label G-I
G: amacrine cell
H: horizontal cell
I: pigmented epithelial layer of retina
Label A-C
A: nuclei of ganglion
B: outer segments of rods and cones
C: choroid
Label D-G
D: axons of ganglion cells
E: nuclei of bipolar cells
F: nuclei of rods and cones
G: pigmented layer of retina
Label A-C
A: optic nerve
B: optic chiasma
C: optic tract
Label D-F
D: lateral geniculate body
E: superior colliculus
F: uncrossed fiber
Label G-I
G: crossed fiber
H: optic radiation
I: occipital lobe (primary visual cortex)
Label J and K
J: superior colliculus
K: lateral geniculate body of thalamus
Label A-C
A: emmetropic eye
B: myopic eye (nearsighted)
C: hyperopic eye (farsighted)
Label A-C
A: external ear
B: auricle (pinna)
C: external acoustic meatus
Label D-F
D: semicircular canal
E: vestibular nerve
F: cochlear nerve
Label G and H
G: cochlea
H: tympanic membrane
Label A-C
A: middle ear
B: internal ear (labyrinth)
C: auditory ossicles
Label D-G
D; malleus
E: incus
F: stapes
G: pharyngotympanic tube
Label A-C
A: Temporal bone
B: semicircular ducts in semicircular canals
C: anterior
Label D-F
D: posterior
E: lateral
F: utricle in vestibule
Label G-I
G: saccule in vestibule
H: stapes in oval window
I: cochlear duct in cochlea
Label J and K
J: cochlear nerve
K: vestibular nerve
Label A-D
A: cochlear duct/scala media (contains endolymph)
B: spiral organ
C: scala vestibuli
D: scala tympani
Label A and B
A: vestibular membrane
B: tectorial membrane
others are on another card
Label A-C
A: tectorial membrane
B: hair (stereocilia)
C: outer hair cells
Label D-F
D: inner hair cells
E: basilar membrane
F: fibers of cochlear nerve
Label A-C
A: stapes
B: oval window
C: scala vestibuli
Label D-F
D is asking what is inside the space
D: perilymph
E: fibers of cochlear nerve
F: round window
Label G-I
G: scala tympani
H: basilar membrane
I: cochlear duct
Label J and K
J: base
K: apex
Label A-C
A: otolith membrane
B: kinocilium
C: stereocilia
Label A-C
C is asking what is in the space
A: membranous labyrinth
B: crista ampullaris
C: endolymph
Label D-G
D: ampulla
E: ampullary cupula
F: hair bundle (kinocilium + stereocilia)
G: hair cell
