special senses - eyes Flashcards
short, coarse hairs overlying above the eye that shade the eyes and keep perspiration out
eyebrows
help protect text the eye from physical danger as well as from drying out
eyelids (palpebrae), eyelashes, and their associated glands
secret dilute saline solution that cleanses and protects the eye as it moistens it, and ducts that drain excess cloud into the nasolacrimal duct
lacrimal glands
secrete acidic sweat to kill bacteria, lubricate eyelids, and moistens with oils
ciliary and meibomian glands
transparent mucous membrane that lines the eyelids and the whites of the eyes, produces a lubricating mucus that prevents the eye from drying out
conjunctiva
white, connective tissue, anchors and protects
sclera
allows for light to pass through (refracts, or bends, light slightly)
cornea
the colored part of the eyes, involuntary muscles to dilate pupil
iris
center al opening of the iris
pupil
bright light, close vision
pupils construct/get smaller
dim light, distant vision
pupils dilate/ get bigger
changes in emotional state
pupils dislate/get bigger
movement of eye controlled by
• abducens
• oculomotor
• trochlear nerves
• a plasma like fluid that fills the anterior segment
• supports, nourishes, and removes wastes
aqueous humor
• avascular, biconcave, transparent, flexible structure that can change shape to allow precise focusing of light on the retina
• REFRACTS LIGHT GREATLY
lens
• gel like substance behind the lens
• keeps he eye from collapsing
vitreous humor
process by which eye detects light energy
photoreception
highly sensitive and are best suited to night vision/dim light, help with peripheral vision
rods
less sensitive to light and are best adapted to bright light and color vision
cones
_____ contain a light absorbing molecules called ______
retinal (vitamin A sub)
• run along the inner surface of the retina
• leave the eye as the optic nerve
ganglion cell axons
• site where the optic nerve leaves the eye
• lacks photoreceptors (the blind spot)
the optic disc
layer where photoreceptors and glial cells captor light and convert it into electrical signals
retina
