Lab 6 Flashcards
skin has a variety of sensory receptors that respond to different..
types of external stimuli
free nerve endings?
branching tips of sensory nerves, respond to touch, pain, temp, most common receptor
tactile discs?
extremely sensitive to fine touch and light pressure
tactile corpuscles?
respond to fine touch and light pressure, especially in eyelids, lips, fingertips
lamellated corpuscles?
respond to deep pressure in skin, muscles, joint capsules,
ruffini corpuscles?
respond to pressure and distortion in dermis
are the cutaneous receptors for pressure phasic or tonic?
phasic except pain
pain receptor (nociceptors) are tonic of phasic?
tonic
phasic receptor vs tonic
phasic= strong response at first, rapidly declines tonic= continue to fire with stimulation
what is it called when pain can be felt in a region different from the site of the stimulus?
referred pain (brain freeze) examples, heart attack causing pain to shoulder
pancreatic pain causing pain in back
thought to happen when nerve fibers from regions of high sensory input, like the skin, and nerve fibers from normally low input happen to converge on the same levels of the spinal cord
vision organ
eye/retina
hearing organ
ear/cochlea
balance organ
vestibule/semicircular ducts/ear
olfaction organ
nose
gustation organ
taste buds/tongue
outer ear consists of?
auricle or pinna, external auditory canal
middle ear consists of?
auditory tube, malleus, incus, stapes
inner ear consists of?
oval window, cochlear duct, basilar membrane, hair cells, semicircular, vestibule
nerve deafness means?
cochlea or cochlear nerve is damaged
conduction deafness means?
tympanic membrane or ossicles are damaged
fibrous tunic?
sclera, cornea; outermost layer
vascular tunic?
choroid, ciliary body, iris; blood vessels, middle layer
neural tunic?
retina, innermost layer, absorbs light
which of the structures contain sensory receptors for light?
neural tunic because retina
structures in the eye responsible for retraction?
lens, vitreous body, cornea
point on the retina where image is seen with greatest clarity?
fovea centralis
cornea and lens act as a cornex, meaning?
images formed by convex lenses are inverted
emmetropia, hypertropia, myopia
emme- normal eye
hyperopia- farsightedness
myopia- nearsightedness
refraction of light =?
bending of the light as it passes through eye
what happens to the near focus as we age?
near focus gets further away with increasing age
how many different cones are there?
3, each respond maximally to a different colour; red, blue, green
what is the blind spot?
spot on the optic disc with no rods and cones
where is the optic disc relative to the fovea?
optic disc is medial to the fovea
what type of photoreceptor is needed for perception of colour?
cones
where in the retina do you have the greatest concentration of cones?
center because the most cones are in the fovea in the center of the eye
why are objects in the peripheral vision visible, but unclear?
there are more rods in the peripheral- rods detect in low light but do not make it clear as to what you are seeing
