Chapter 13 Flashcards
What are the five special senses?
- Smell
- Taste
- Hearing
- Blance
- Sight
What CN’s are involved with the special sense’s? Name there number and to what special sense they belong.
- Vision: Optic Nerve #2
- Smell: Olfactory Nerve #1
- Hearing: Vestibulocochlear Nerve #8
- Balance: Vestibulocochlear Nerve #8
- Taste: Glossopharyngeal Nerve #9, Facial nerve #7, Vagus #10
Name what makes the five sense’s react with their sensory receptors.
- Vision: light
- Smell: chemicals
- Taste: chemicals
- Balance: Mechanical
- Hearing: Mechanical
What for Olfactory’s sensory receptor?
Hairs.
Where are most taste buds located?
The epithelium of the papillae.
What can taste buds be found?
Lips, tongue,palate, throat
What are the five basic types of taste?
- salty
- sour
- sweet
- bitter
- umami
Which taste are we most sensitive to and why?
bitter, because they are poisons.
What does the visual system consist of?
- eye: eyeball, optic nerve
- accessory structures: eyebrows, eyelids, conjunctiva, lacrimal apparatus, and extrinsic eye muscles
- sensory neurons
Explain the lacrimal tear secretion.
- Tears are produced in the lacrimal gland
- Enter the eye via superolateral excretory ducts
- Exit the eye medially via lacrimal canailculi
- Drains into the nasolacrimal duct
What is in located in the fibrous tunic of the eye?
sclera, cornea
What is located in the vascular tunic of the eye?
choroid, ciliary body, iris, pupil
What is located in the sensory tunic?
retina, macula lutea, fova centralis, optic disc
What does the ciliary body do? **
regulates the shape of the lens.
What does the iris do? **
regulates the amount of light entering the eye by changing the size of the pupil.
Macula lute only have?
Mostly cones, and a little amount of rods.
The fova centralis has the highest number of what?
cones.
The optic disc is also called ___________ and has no ________?
blind spot, photoreceptors
Cones are responsible for what kind of vision?
color
Rods are responsible for what kind of vision?
black and white
Ganglion cells axons leave the retina at the ________ to form ________, ________, ________.
optic disc, optic nerve, optic chiasm, optic tract.
Is the lens vascular or avascular?
avascular.
What does the lens do? What is it composed of?
focuses the light on the retina. epithelium and lens fibers.
What does the anterior cavity contain?
aqueous humor, and it is located from the cornea to the lens. It also removes waste.
What does the posterior cavity contain?
vitreous humor, and is located from the back of the lens to the back of the eye. It also maintains the shape of the eye ball, press of the eye. Holds the lens in place, and helps with the refraction of light.
What are the functions of the eye?
refraction - bending of light rays
***Visual Axis- visual pathway through the eye
What is the visual pathway through the eye (Visual Axis)?
Visual Axis > Cornea > Anterior Segment w/aqueous humor > pupil > lens > Posterior Segment w/vitreous humor > retina
What is emmetropia?
Normal vision
What is myopia?
Near sightedness
What is hyperopia?
Far sightedness
What are the three events that must happen to bring an image into focus?
- accommodation by the lens
- constriction of the pupil
- convergence of the eyes
What activates rhodopsin? What happens to it when the light hits it?
exposer to light. it splits into opsin and retinal, eventually resulting in an action potential.
Light adaptation is caused by?
The reduction of rhodopsin.
Dark adaptation is caused by?
The production of rhodopsin.
What colors can cones be?
Red, Blue and Green
Most rods are located in what part of the retina?
periphery
What are the three parts of the ear?
- external ear
- middle ear
- inner ear
Which parts of the ear are involved with hearing?
the external and middle.
Which parts of the ear are involved with hearing and equilibrium?
The inner ear only.
Where does the external ear begin and end?
Begins from the outside of the head to the tympanic membrane.
Where is the middle ear?
It is the air filled cavity
Where is the inner ear?
It is the set of fluid filled chambers.
What are the parts of the external ear?
The external auditory canal. (auricle)
Tympanic membrane
What are the parts of the middle ear?
M.I.S - Malleus, Incus, Stapes Eustachian tube (this tube equalizes the pressure in the middle to the outside pressure.)
What are the parts of the inner ear?
Cochlea (hearing) Semicircular canal(dynamic balance) Vestibule(static balance)
What do we bend to generate as action potential? **
stereocillia
Where is the location of the organ of court?
the spiral organ - which is the location for hair cells.
The vestibularcochlear nerve runs to the ear by?
hair cells
Pitch is determined by?
frequency of sound waves
Volume is determined by?
amplitude of sound waves
High pitch sound are closer to?
The oval window
Low pitch sounds are farther away from?
The oval window.
The round window does what? Where is it?
It stops sound waves, and is at the in of the tympanic duct.