Practical #1 Flashcards
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
sclera
white, opaque outer layer of the eye
cornea
clear tissue that covers the front of the eye
choroid
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
ciliary muscles
control lens shape
ciliary processes
secrete aqueous humor
ciliary zonule
hold lens upright
iris
visible colored part of the eye. Controls diameter and size of pupil
Pupil
regulates the amount of light entering the eye
retina
photoreceptors, cones ( day vision) and rods (night vision)
optic disc
where the optic nerve exits the eye; lacks photoreceptors “blind spot”
fovea centralis
contains cones only, bipolar and ganglion layers pushed aside. Region of greatest visual acuity
lens
flexible, transparent, biconvex disc that focuses light onto the retina by changing shape
vitreous humor
located in the posterior segment. Transmits light, holds the retina and lens in place
tapetum lucidum
allows cows to see at night (night vision)
Where is the crista ampullaris located?
semicircular canal in the ear (equilibrium)
crista ampullaris
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