Exm 4 (ch 17) Flashcards
respond to stimulus from outside the body such as
touch or temperature
Exteroreceptors
detect changes away from the body such as the eye and ears
Teloceptors
detect changes within the body
Interoreceptors
olfaction, gustation, “common chemical sense”
Chemical senses
chemical irritants found in mucus membranes
• Ex: tear gas, acid fumes, onions
Common chemical sense 
Smell is a
Chemical sense
The olfactory epithelium covers the inferior surface of the_______(of the ethmoid bone of the skull) and extends along the superior nasal concha
cribriform plate
located in the mucous membrane lining the nose. Used for physical support, nourishment and electrical insulation for olfactory receptor cells
Supporting cells (columnar epithelium)
Undergo mitosis to replace olfactory receptor cells
Basal stem cells 
Produce mucus that is used to dissolve odor molecules so that transduction may occur, basically the mucus dissolves the “smells”
Olfactory glands (Bowman’s glands)
Receptors in the nasal mucosa send impulses along branches of
olfactory (I) nerve
binding of an odorant molecule to an
olfactory receptor protein
Olfactory transduction
There are only 5 primary tastes:
o Sour
o Sweet
o Bitter
o Salt
o Umami (meaty, savory)
There are three types of smelling cells
- Olfactory receptor cells
- Supporting cells
- Basal cells
Taste buds contains three kinds of epithelial cells
o Supporting cells
o Gustatory receptor cells
o Basal stem cells
Taste buds are located in elevations on the tongue called
papillae
about 12 that contain 100–300 taste buds. Back of tongue
Vallate papillae
scattered over the tongue with about 5 taste buds each. All tongue
Fungiform papillae
located in lateral trenches of the tongue (most of their taste buds
degenerate in early childhood).
Foliate papillae
cover the entire surface of the tongue
• Contain tactile receptors but no
taste buds!!
• Increase friction to make it easier for
the tongue to move food within the
mouth. Cats
Filiform
What cranial nerve carries taste information from the anterior 2/3 of the tongue
Facial VII
What cranial nerve carries taste information from the posterior 1/3 of the tongue
Glossopharyngeal (IX)
What cranial nerves carries taste information from taste buds on the epiglottis and in the throat
Vagus (X)
uses visible light which is part of the electromagnetic spectrum with wavelengths from about 400 to 700 nm
Vision
is defined as the distance between two consecutive peaks of an electromagnetic wave
Wavelength
protect eyes and keep them moist
Eyelids (palpebra)
Prevent dust, or particles from getting in the eye 
Eyelashes 
Helps deflect sunlight and keep perspiration (sweat) out
Eyebrows(superciliary/superorbital)
pink mass of tissue in the medial
canthus. Collects tears
Lacrimal caruncle
corner next to nose
Medial commissure/medial canthus:
corner away from the nose
Lateral canthus/lateral commissure
control eyelid movement
Palpebral muscles
are responsible for moving
the eyeball itself in all directions
extrinsic eye muscles
is a thin, protective mucous membrane that lines the eyelids and covers the sclera
The conjunctiva 
A fold of connective tissue that gives form to the eyelids. Contains a row of sebaceous glands (tarsal glands/Meibomian glands) that keeps the eyelids from sticking to each other
The tarsal plate
_______, secretes tears into.
_______, which distribute tears over surface of eyeball.
_______, drain tears into.
_______, which drains tears into.
________, which drains tears into.
Nasal cavity.
Lacrimal gland. Excretory lacrimal ducts. Superior or inferior lacrimal canaliculi. Lacrimal sac. Nasolacrimal duct.
The six extrinsic eye muscles
superior rectus, inferior rectus, lateral rectus, medial rectus, superior oblique and inferior oblique
Superior rectus
Looking up
Inferior rectus
Looking down 
Lateral rectus
Looking lateral
Medial rectus
Looking medial 
Superior oblique
Trochlear nerve 
Inferior oblique
Laterally and down 
the cornea and sclera
Fibrous tunic
the choroid, ciliary body and iris
Vascular tunic
______ as sphincter pupillae muscles of iris contract
Pupil contracts
______ as dilator pupillae muscles of iris contract
Pupil dilates
admits and refracts (bends) light
Cornea
provides shaped and protects inner parts
Sclera
regulates the amount of light that enters the eyeball, eye color
Iris
the opening in the iris where light passes through
Pupil
secretes aqueous humor and alters the
shape of the lens (accommodation)
Ciliary body
provides blood supply and absorbs scattered light
Choroid
receives light and converts it to receptors potentials
Retina
retracts light. Can change shape
Lens
aqueous humor
Anterior section
Vitreous humor
Posterior segment
The point at which the optic nerve exits
the eye is the
optic disc (blind spot)
The exact center of the retina is the
Macula lutea
In the center of macula lutea is the
fovea centralis (area of highest visual acuity)
The retina contains sensors
(_______) known as rods and cones
photoreceptors
Is used to see dim light
Rods
Is used to produce color vision
Cones
Do rods or cones have a higher visual acuity
Cones
The anterior and posterior chamber by the iris are filled with white liquid
Aqueous humor
The posterior cavity of the eye is filled with what fluid
Vitreous humor
pressure builds when aqueous humor is produced faster than it is reabsorbed
Glaucoma
Light _______when it passes through a transparent substance with one density into a second transparent substance with a different density. This bending occurs at the junction of the two substances
refracts (bends)
The lens______ the differences between viewing near and far objects by adjusting it’s width.
accommodates
The normal _______eye will refract light correctly and focus a clear image on the retina
(emmetropic) . “Normal” 20/20 vision
In cases of______ (nearsightedness)
the eyeball is longer than it should be
and the image converges (narrows
down to a sharp focal point) in front of
the retina. These people see close
objects sharply, but perceive distant
objects as blurry
myopia
A_____ lens is used to correct the
vision of myopia
concave. Diverging
In cases of______ (farsightedness)
also known as xxx, the
eyeball is shorter than it should be and
the image converges behind the retina
hyperopia
A_____ lens is used to correct this
abnormality (hyperopia)
convex
_____is a condition where
either the cornea or the lens (or
both) has an irregular curve
• _______ causes blurred or
distorted vision
Astigmatism
Rods contain only
rhodopsin- a chemical
Cones contain three different photopigments, one for each of the three types of cones (____)
red, green, blue
Photopigments associated with vision contain two parts: a glycoprotein____ and a derivative of vitamin A called ____
opsin, retinal
occurs when an individual moves from dark surroundings to light ones
o It occurs in seconds
Light adaptation
takes place when one moves from a lighted area into a dark one
o This takes minutes to complete
Dark adaptation
Part of this difference is related to the rates of____ and _____ of
photopigments in rods and cones
o Light causes rod photoreceptors to decrease their release of the inhibitory
neurotransmitter glutamate
bleaching, regeneration
In darkness, rod photoreceptors release the inhibitory neurotransmitter______. This inhibits bipolar cells from transmitting signals to ganglion cells which provide output from the retina to the brain
glutamate
The anterior location of our eyes leads to visual field overlap. This gives us _____
binocular vision
Vision from the medial nasal fields are
processed by the
lateral retina
The lateral temporal fields are processed by the
medial retina
Temporal vision»_space;»optic chiasm
Notes
The external (outer) ear contains the
auricle (pinna), external auditory
canal, and the tympanic membrane
(eardrum)
The______ collects
vibrating sounds from the external
ear and separates the outer and
middle ear
tympanic membrane
____glands secrete
cerumen (earwax) to protect the
canal and eardrum
Ceruminous
Middle ear bones
Malleus, incus, and stapes(smallest)
Sound vibrations are transmitted from the eardrum through these 3 bones to the
oval window
The ________ extends from the middle ear into the nasopharynx to
regulate air pressure in the middle ear. Common sight for ear infections in small children
auditory tube (pharyngotympanic
tube, eustachian tube)
_____&______muscles
contract and inhibit movement od the
ossicles to help protect against loud noises. Pressure
Tensor tympani and stapedius
The internal (inner) ear (labyrinth) contains the_____ which translates vibrations into neural impulses that the brain can interpret as sound, and the______ that work with the cerebellum for balance and equilibrium
cochlea, semicircular canals
The bending of the hair cells on the _____is what causes the neural impulse to be transmitted/ sends nerves impulses down the cochlear nerve fibers
Tectorial membrane
The cochlear nerve fibers form the
____of the vestibulocochlear
(VIII) nerve
cochlear branch
Medial. Lateral
Hearing. Vision
maintenance of the body’s position
relative to the force of gravity. Standing up
Static equilibrium
the maintenance of the body’s
position in response to sudden movements.moving
Dynamic equilibrium
The organs that maintain
equilibrium. Includes saccule, utricle (both otolithic
organs), and semicircular canals.
Vestibular apparatus
thickened wall in each part of the membranous labyrinth
Macula
Three semicircular canals are responsible for _____which allows us to maintain orientation
dynamic equilibrium
Around the age of 40 the lens begins to lose elasticity and has difficulty
focusing on close objects. Ex: mom holding phone away from her face
Presbyopia
