Chapter 17 sense organs Flashcards
What is the normal adjustment of the eye to focus on objects from far to near?
Accommodation
What is the area behind the cornea and in front of the lens and iris
Anterior chamber
What is the fluid produced by the ciliary body and found in anterior chamber?
Aqueous humor
What term means consisting of two surfaces that are rounded, elevated, and curved evenly (like lens of eye)
Biconvex
What is the middle vascular layer of the eye, between the retina and the sclera
Choroid
What is the structure surrounding the lens that connects the choroid and iris that controls the shape of the lens and secretes aqueous humor
Ciliary body
What is a photoreceptor cell in the retina that transforms light energy into a nerve impulse, and is responsible for color and central vision
Cone
What is the delicate membrane that lines the undersurface of eyelids and covers anterior eyeball
Conjunctiva
What is the fibrous transparent layer of clear tissue that extends over the anterior portion of the eyeball
Cornea
What is the tiny depression in the retina that is the region of clearest vision
Fovea centralis
What is the posterior inner part of the eye
Fundus of the eye
What is the pigmented layer that opens and closes to allow more or less light into the eye
Iris
What is the transparent, biconvex body behind the pupil of the eye
Lens
What is the yellowish region on the retina lateral to and slightly below the optic disc
Macula
What is the point at which optic nerve fibers cross in the brain
Optic chiasm
What is the region at the back of the eye where the optic nerve meets the retina, blind spot
Optic disc
What is the cranial nerve carrying impulses from the retina to the brain?
Optic nerve
What is the central opening of the eye surrounded by the Ir is which light rays pass?
Pupil
What is the bending of light rays by the cornea, lens, and fluids of the eye to bring the rays into focus on the retina
Refraction
What is the light sensitive nerve cell layer of the eye containing photoreceptor cells
Retina
What are photoreceptor cells of the retina that are essential for vision in dim light and for peripheral vision
Rod
What is the tough white outer coat of the eyeball
Sclera
What is the relay center of the brain
Thalamus
What is the soft jelly-like material behind the lens in the vitreous chamber
Vitreous humor
What is the inability of the eye to produce a focused image on the fovea or central part of The retina
Astigmatism
When the cornea is steeper in one meridian more than the other or the globe is not round, what occurs?
Visual blurriness
What is farsightedness, where the light focuses behind the retina, because a short eyeball or the refractive power of the lens is too tweak
Hyperopia (hypermetropia)
What is nearsightedness where the eyeball is too long, or the refractive power of the lens is so strong that light rays do not properly focus on the retina
Myopia
In myopia, light rays are focused where on the retina?
In front of
“My” means to what in Greek?
Shut
