Anatomy Test 6
place the structures of the eye in order from superficial to deep.
1. choroid, 2. photoreceptors, 3. horizontal cells, 4. bipolar cells
order these structures in the order that tears travel through them.
1. lacrimal puncta, 2. lacrimal canaliculus, 3. lacrimal sac, 4. nasolacrimal duct
gustatory cells have a _______ lifespan.
7-10 day
which nerve fibers cross in the optic chiasma?
Axons of ganglion cells from nasal halves of both retinas
Which type of receptor detects pressure changes?
Baroreceptors
True or False: Compared to many animals, our olfactory ability is vastly more sensitive and more high developed
False
Match the special sense with its anatomical name
Gustation- Taste Olfaction- Smell Vision- Sight Equilibrium- Balance Audition- Hearing
refraction of light for vision is greatest as light rays pass from ______ into the ______ the difference in their refractive index is maximal.
air, cornea
which are characteristics of the cornea?
avascular and transparent
taste buds are made of gustatory cells, supporting cells, and _______.
basal cells
depth perception is also known as ______ vision.
binocular
in the light, ______ cells are no longer inhibited and therefore release the neurotransmitter glutamate
bipolar
the process is called the bleaching reaction because rhodopsin goes from a ______ color to ______.
bluish-purple, colorless
outer hair cells, near the center of the basilar membrane, will
both magnify vibrations of soft sounds and sharpen pitch perception
what eye disorder causes "milky" vision?
cataracts
_____ are receptors that detect chemicals.
chemoreceptors
Which terms indicate a receptor type that is classified by its modality of stimulus?
chemoreceptors, mechanoreceptors, and thermoreceptors
what is the largest structure of the vascular tunic?
choroid
the iris is continuous with the _______.
ciliary body
prior to being stimulated by light, the retinal portion of rhodopsin is in a bent twisted shaped called _______.
cis-retinal
Hearing organs are housed within the ___________ in the inner ear.
cochlea
A ______ shaped lens is used to treat hyperopia and a ______ shaped lens is used to treat myopia.
convex, concave
the limbus is the junction between the sclera and the ______.
cornea
free nerve endings are terminal branches of _____
dendrites
Cutaneous receptors are a type of
exteroceptors
true or false: Our brain perceives different colors because each cone responds to a different wavelength on the visual spectrum.
false
true or false: astigmatism is also called farsightedness
false
true or false: encapsulated tactile receptors are found in the skin and consist of dendrites within protective coat.
false
true or false: high-pitched sounds produce a peak displacement of the basilar membrane near the apex of the cochlea.
false
when the bipolar cells release their neurotransmitter, the ______ cells propagate a nerve signal along the _____ nerve.
ganglion, optic
what disease causes fluid build up in the eye, dislocating the lens?
glaucoma
as a consequence of the dark current, ______ channels in the photoreceptor open.
glutamate
the ____ segment of each photoreceptor contain organelles for the cell such as mitochondria.
inner
Specific types of receptors called _____ detect stimuli in the internal organs.
interoceptors
place the structures of the vascular tunic in order from anterior to posterior
iris, ciliary body, and choroid
which are examples of encapsulated receptors?
krause bulbs and end bulbs
the lacrimal apparatus produces, collects, and drains ______ fluid.
lacrimal
cataracts area disorder of the _______.
lens
presbyopia occurs when the ______ loses elasticity.
lens
the suspensory ligaments connect the _____ capsule to the ciliary muscles.
lens
what structure focuses incoming light onto the retina?
lens
lacrimal fluid prevents bacterial infection because it contains an antibacterial enzyme called ______.
lysozyme
tactile receptors are a type of
mechanoreceptor
Tactile receptors are a type of
mechanoreceptors
the fat surrounding the eye is called _______ fat.
orbital
The _____ segment of each photoreceptor is composed of hundreds of discs containing photopigments that are capable of absorbing light energy.
outer
accommodation is controlled by the _____ division of the nervous system.
parasympathetic
the sphincter papillae is controlled by the ________ division of the nervous system.
parasympathetic
Which type of receptor is found in skeletal muscles, tendons, and joint capsules?
proprioceptors
_____ include only the somatic sensory receptors within joints, muscles, and tendons.
proprioceptors
The sclera ________.
provides for eye shape and is made of dense connective tissue
As tears drain, through the lacrimal caruncle, they enter small holes called the lacrimal _________
puncta
the area that a receptor cell gathers information from is called the ______.
receptive field
Gustatory cells are found in taste ____.
receptors
the apparent distortion of the spoon in the water glass is due to the phenomenon called _____.
refraction
what structure makes up the posterior 5/6 of the fibrous tunic?
sclera
Receptors for general senses are distributed throughout the _____ and viscera.
skin
Olfaction is the sense of __________.
smell
the ciliary muscles are made of _____ muscle.
smooth
axons from the optic tract project to the _____ colliculi.
superior
what is the most numerous type of receptor?
tactile receptors
a feature common to all receptors is
the ability to respond to a stimulus
Which would stimulate somatic nociceptors?
touching a hot pan, sprained ankle, and exposure to acid on the skin
true or false: macular degeneration is the leading cause of blindness in developed countries.
true
true or false: the ampler grid is used to test for macular degeneration.
true
true or false: there is currently no cure or macular degeneration
true
true or false: walking into a room and recognizing the smell if a favorite dish is an example of a sensation
true
What type of papillae is largest and least numerous?
vallate
the papillae that are fewest in number, but contain the most taste buds, are the _____ papillae.
vallate
the brain can determine the static position of the head due to sensors in the _____
vestibule
the posterior cavity contains the _______ humor.
vitreous
true or false: rods and cones face the light coming into the eye
false
true or false: the majority of macula degeneration cases are found in adolescents.
false
what is the margin between the photosensitive and non photosensitive regions of the retina called?
ora serrata
Where are end bulbs located?
oral and nasal cavities
where is the trans-retinal transported so that the retinal can be reconverted back to its cis formation?
pigment epithelium
as we adjust to low light, our ______ become nonfunctional and it may take ______ for rhodopsin to become generated sufficiently so that you can see well in low-light conditions.
cones, 20-30 minutes
what is the name of the outermost layer of the eye?
fibrous tunic
a detached retina is caused by a separation between which two layers?
pigmented layer of the retina and neural layer of the retina
the ora serrata extends anteriorly from the _______.
retina
a lack of photoreceptors in this structure creates the "blind spot"?
optic disc
what is the space behind the lens called?
posterior cavity
Tactile cells are associated with
tactile discs
what color is the macula lutea?
yellow
when light stimulates the photoreceptors, the ______ cells become depolarized and release the neurotransmitter _______.
bipolar, glutamate
when elevated levels of cGMP are present, NA+ channels in the photoreceptor membrane are kept open and Na+ enters the photoreceptors. This is called the _______.
dark current
light rays are refracted or bent when they pass through two media of different _________.
densities
Emmetropia Hyperopia Myopia
normal vision farsightedness nearsightedness
ganglion axons of the retina converge to form the _______ nerve.
optic
the regeneration of ________, in cones occurs much more quickly than the regeneration of ______ in rods; therefore, cone cells are not as negatively affected by bright light as rods.
photopsin, rhodopsin
the process by which photoreceptors become activated when the photopigments are altered by light entering the eye is _______.
phototransduction
root hair plexuses are usually found in the
reticular layer of the dermis
what type of photoreceptors detect color?
cones
optic tracts extend to which structures after they leave the optic chiasm?
superior colliculi and lateral geniculate nucleus of the thalamus
the muscle that primarily functions to pull the eye superiorly and secondarily functions to move the eye medially is the _____ ______ muscle.
superior rectus
What type of phasic receptors detect light touch, shapes, and textures?
tactile corpuscles
which events occur during bright light adaptation?
cones gradually adjust, rods become inactive, and pupils constrict
rods are essentially nonfunctional in bright light because ______.
in bright light, rhodopsin will bleach as fast as it is reformed.
accommodation is the process of making the lens ________.
more spherical