exam 2 Flashcards
eyeball sits in
bony orbit of skull
eye layers
fibrous, vascular, sensory
eye outermost layer
fibrous
eye fibrous layer includes
sclera, cornea
sclera and cornea functions together
shape eye, support deeper structures
sclera comprises ___% of fibrous layer
85
sclera provides
attachment for extraoccular muscles
extraoccular muscles for
movement
white part of eye
sclera
transparent outer covering of eye
cornea
light entering the eye is refracted here
cornea
vascular layer includes (3 general/major)
choroid, ciliaries, iris
choroid consists of
CT, blood vessels
choroid function
nourishment to outside layers of retina
ciliary body includes
ciliary muscle, processes
ciliary body function
control shape of eye
ciliary muscle: ___ muscle fibers arranged in ___, ____ and ___
smooth
longitudinal, circular, radial
ciliary processes attach ___ to ___ via zonular fibers
lens, ciliary body
zonular fibers make up
suspensory ligament
accommodation
ciliary muscle contract, body shortens, fiber slacken, reduce tension applied to outside of lens, become more rounded
ciliary muscle relaxed, body ___, fibers ___, pull lens ___
greater, tighter, flat
what allows long distance vision
muscle relax, pull lens flat
iris
circular, pupil in center
eye color
iris
circular fibers are ____ papillae muscle innervated by ____
sphincter, parasympathetic NS
what causes constriction of the pupil
iris, circular fibers
radial fibers are ___ papillae innervated by ____
dilator, sympathetic NS
dilation ___ light
increases
inner light detecting part
retina
2 layers of retina
neural, pigmented
neural layer contains
photoreceptors
neural layer is located
posteriorly and laterally
pigmented layer ___ neural layer
under
pigmented layer attached to
choroid
pigmented layer continues, neural does not –> _____ retina
non-visual
optic part contains which retina layer(s)
both
center of the retina marked by
macula lutea
macula lute made of
fovea centralis
fovea centrals high concentration of
cones
optic disc
blind spot
optic disc created by
optic nerve entering retina
central retinal artery enters here
optic disc
chamber between cornea and iris
anterior
chamber behind iris anterior to lens
posterior
which chamber contains suspensory ligaments
posterior
chambers are continuous with one another by
pupillary opening
clear plasma like fluid
aqueous humor
aqueous humor function
nourish, protect eye
aqueous humor is first secreted in the ____ chamber and flows to ___ chamber via the ___
posterior, anterior, pupil
aqueous humor is absorbed into
canal of schlemm
canal of schlemm
scleral venous sinus
if drainage of aqueous humor is interrupted
intra occular pressure increases
glaucoma
intraoccular pressure increases, aqueous humor is not drained
lens separates chambers from
vitreous chamber
vitrous chamber function
fills eye with vitreous humor
anosmia
partial or complete loss of smell
anosmia can come from
head trauma, respiratory infections, old age
transduction
sensory cells translating chemical, electromagnetic, mechanical stimuli into action potentials
photoreceptors detect
light waves
mechanoreceptors detect
sound waves and pressure on the skin and inner ear
gustation
taste
olfaction
smell
gustation and olfaction: ___receptors
chemo
chemoreceptors detect
molecules in food and air
most primitive and fundamental senses
taste, smell
gustation/olfaction is powerful at activating
memories, triggering emotions and alerting danger
sniff smell–> odor is ___
volatile
volatile
gaseous state
most smell molecules are filtered out on the way up the
nasal cavity
back of nose contains ___ epithelium
olfactory
olfactory epithelium
small yellowish patch of tissue on the roof the nasal cavity
olfactory epithelium contains ___ sensory neurons
olfactory
olfactory sensory neurons are surrounded by
insulating columnar supporting cells
smell molecules dissolve in
mucus
when molecules are in mucus, bind to receptors on ____, fire AP through ___ bone, into ____ in brain
olfactory sensory neurons, ethmoid, olfactory bulb
each neuron has receptors for ____ kind of smell
one
smell signal travels down axon, converge with other cells creating
glomerulus
glomerulus means
ball of yarn
transfer station of olfaction
glomerulus
mitral cell
relay signal to brain
mitral cell: each cell any # of ____ synapsing with it
olfactory axons
each olfactory axon represents and identifies
single volatile chemical
how many olfactory receptor neurons are there
40 mil
olfactory tract to ____ in brain
olfactory cortex
olfaction: frontal cortex
identified
emotional ground control for
emotions
two pathways smell can take in brain
frontal cortex, limbic system
emotional ground control speed
fast, intense
taste is ___% smell
80
taste comes from
as we chew, air is forced up nasal passage
taste buds are actually
fungiform papillae
tastes register in ___ parts of the tongue
all
taste buds are tucked in
pockets
each bud has ___ taste receptor cells
50-100
epithelial cells on the tongue synapse to
sensory neurons
gustatory cells
do the tasting
gustatory cells project
gustatory hair
gustatory hair is
taste pore
___ cells replace gustatory
basal
basal cells are
dynamic
tastants
food chemicals
tastants dissolve in ___, diffuse through ___, bind to receptors on ___ and trigger AP
saliva, taste pores, gustatory cells
salty tastes come from
Na+ channels opening generating graded potential, sparking ap
sour/acidic tastes come from
H ions, activate proton channels
AP is triggered, taste message related through which cranial nerves
facial, glossopharyngeal, 10
eyes scan our environment for
cues to where we re in relation to the objects around us
___ continuously sample the position of our limbs in space
proprioceptors
vestibule function
confine chaos, sense acceleration, allow brain to understand movement
“organ of balance”
vestibule
vestibule sits in _____ within petrous part of ___ bone
labyrinth of canals, temporal
linear acceleration
forwards, backwards, side to side, up and down
3 axis of movement
x, y, z
