Special Senses Flashcards
Purpose of the sense
Protection (primary) and survival
General senses
Visceral, tactile, temperature, nociception, proprioception
T/F visceral sensation is poorly localized
True
T/F taste, smell. Hearing, and vestibular all use hair cells in the production of impulses to the brain
True
Special senses
Sight, auditory, taste, vestibular, olfactory
What are the types of scent animals can have
Macrosmatic, microsmatic, anosmatic
Why is it more difficult to smell if your nose is dry?
Hair cells detect soluble chemicals, so need hydration
Two types of vestibular balance
Static and dynamic
What is static balance and how does it work
When you are standing still otoliths in the macule pull on the hair to tell you which direction gravity is
How does dynamic balance work
Fluid in the semicircular canals displaces capula and hair cells
What is light refraction
Light bends perpendicular to the surface it comes out of
What does the fibrous outer layer of the eye consist of
Sclera, cornea, limbus
What structures are part of the uvea of the eye
Choroid, iris, ciliary body
Where is the tapetum located and what is it’s purpose
On the choroid, reflects light back onto the retina to enhance low light vision
What is lens accomodation
The smooth muscle of the ciliary body pull on the suspensory ligaments and change the shape of the lens to focus on near/ far objects
What is the shape of the lens relaxed
Elliptical
What happens to light when it goes through the lens
Slows down and changes direction
What do the rods do
Sense dark and light
What do the cones do
Sense color
What structures produces aqueous humor
Ciliary body
List the route of aqueous humor
Produced by the ciliary body in the posterior chamber, flows through the pupil into the anterior chamber, then gets carried away by blood vessels in the sclera
Where is the anterior chamber located
Directly posterior to the cornea
What two structures are important for tear production
Nictitans gland and lacrimal gland
Structures of the palbebra
Dorsal and ventral palbepra. Lateral and ventral canthis
Tear production
Cornea gets nutrition from tears produced by the nictitans and lacrimal gland
Tear drainage
Dorsal and ventral lacrimal puncta at the medial canthis that drains through the nasolacrimal duct
What are the oblique rectus muscles responsible for
Rotating the eye
What is the retractor bulbi responsible for
The nictitans gland
Anatomy of the external ear
Pinna, vertical canal, horizontal canal
Anatomy of the middle ear
Tympanic membrane, auditory ossicles, eustachian tube. Tympanic cavity
Anatomy of the inner ear
Oval window, round window, bony labyrinth, membranous labyrinth, cochlea, organ or corti
What is the purpose of the tympanic membrane
Boundary between outer and middle ear. Converts sounds waves to mechanical vibrations via the ossicles
What structures helps in equalizing pressure
Eustachian tube
What is impedence matching
Fluid waves generated by sound waves
How are nerve endings stimulated in the ear
Perilymph waves transmitted from the scala vestibuli pass across the membrane to the endolymph in the second scala medii. This initiates movement at the organ or corti which stimulates nerve endings that create impulses that are sent to the brain
Describe the structures light goes through in the eye
Cornea, iris, lens. Retina, optic nerve
What structures in the eye slow down light
Cornea, aqueous humor, lens, vitreous humor.
