Flashcards in Practical #1 Deck (34)
Lateral rectus muscle
moves eye laterally
Medial rectus muscle
moves eye medially
Superior rectus muscle
elevates eye and turns it medially
inferior rectus muscle
depresses eye and turns it medially
Superior oblique muscle
depresses eye and turns it laterally
Inferior oblique muscle
elevates eye and turns it laterally
white, opaque outer layer of the eye
clear tissue that covers the front of the eye
posterior of vascular layer. blood vessels supple all layers of the eye. Contains melanin that absorbs light to prevent scattering
where is the ciliary body located?
anterior to choroid
control lens shape
secrete aqueous humor
hold lens upright
visible colored part of the eye. Controls diameter and size of pupil
regulates the amount of light entering the eye
photoreceptors, cones ( day vision) and rods (night vision)
where the optic nerve exits the eye; lacks photoreceptors "blind spot"
contains cones only, bipolar and ganglion layers pushed aside. Region of greatest visual acuity
flexible, transparent, biconvex disc that focuses light onto the retina by changing shape
located in the posterior segment. Transmits light, holds the retina and lens in place
allows cows to see at night (night vision)
Where is the crista ampullaris located?
semicircular canal in the ear (equilibrium)
responds to changes in the velocity of rotational head movements
Which parts of the ear considered to be external?
auricle, external acoustic meatus, and tympanic membrane
Which components are considered to the middle ear?
tympanic cavity, tensor tympani muscle, auditory tube, auditory ossicles (malleus, incus, and stapes)
Which components are considered to the internal ear?
cochlea, vestibule, semicircular canals (lateral, anterior and posterior), oval window, round window, and vestibulocoholear nerve
Which regions of the internal ear are involved with hearing? equilibrium?
EQ: vestibule, semicircular canals
what are the 3 major types of sensory inputs used to maintain body eq and balance?
internal ear (vestibular apparatus), vision, and proprioreceptors in muscles and tendons
What is the equation for hematocrit percentage?
RBC height divided by total blood volume x 100