The Eye Terms Flashcards
Aqueous Humor
Watery fluid filling spaces between cornea and lens
Choroid
Middle layer of eyeball; this layer provides blood supply for eye
Cilia
Term for eyelashes that protect eye from foreign particles or for nasal hairs that help filter dust and bacteria out of inhaled air
Ciliary Body
Intraocular eye muscles that change shape of the lens
Cones
Sensory receptors of retina that are active in bright light and see in color
Conjunctiva
Protective mucous membrane lining on underside of each eyelid and across anterior surface of each eyeball
Cornea
Portion of sclera that is clear and transparent and allows light to enter interior of eye; also plays role in bending light rays
Eyeball
Eye by itself, without any appendages such as eye muscles or tear ducts
Eyelashes
Along upper and lower edges of eyelids; protect eye from foreign particles; also called ‘cilia.’
Eyelids
Upper and lower fold of skin that provides protection from foreign particles, injury from sun and intense light, and trauma; both upper and lower edges of eyelids have small hairs or cilia; in addition, sebaceous or oil glands are located in eyelids which secrete lubricating oil
Eye Muscles
There are six muscles that connect eyeball to orbit cavity; muscles allow for rotation of eyeball
Fovea Centralis
Area of retina that has sharpest vision
Iris
Colored portion of eye; can dilate or constrict to change size of pupil and control amount of light entering interior of eye
Lacrimal Apparatus
Consists of lacrimal gland, lacrimal ducts, and nasolacrimal duct
Lacrimal Ducts
Tear ducts located in inner corner of eye socket; collect tears and drain them into lacrimal sac
Lacrimal Gland
Gland located in outer corner of each eyelid; washes anterior surface of eye with fluid called tears
Lens
Transparent structure behind pupil and iris; functions to bend light rays so they land on retina
Macula Lutea
Area of retina onto which straight ahead images are projected
Mucous Membrane
Membrane that lines body passages that open directly to exterior of body, such as mouth and reproductive tract, and secretes thick substance, or mucus
Nasal Cavity
Large cavity just behind external nose that receives outside air; covered with mucous membrane to cleanse air; nasal septum divides nasal cavity into left and right halves
Nasolacrimal Duct
Duct that collects tears from inner corner of eye socket and drains them into nasal cavity
Oblique Muscles
Oblique means slanted; two of eye muscles are oblique muscles
Ophthalmology (Ophth)
Branch of medicine specializing in condition of eye
Optic Disk
Area of retina associated with optic nerve; also called ‘blink spot.’
Optic Nerve
Second cranial nerve that carries impulses from retinas to brain
Pupil
Hole in center of iris; size of pupil is changed by iris dilating or constricting
Rectus Muscles
Rectus means ‘straight’; four of eye muscles are rectus muscles
Refracts
Bending of light rays as they enter eye
Retina
Innermost layer of eye; contains visual receptors called rods and cones; rods and cones receive light impulses and transmit them to brain via optic nerve
Retinal Blood Vessels
Blood vessels that supply oxygen to rods and cones of retina
Rods
Sensory receptors of retina that are active in dim light and do not perceive color
Sclera
Tough protective outer layer of eyeball; commonly referred to as ‘white of eye.’
Sebaceous Glands
Also called ‘oil glands’; produce substance called sebum that lubricates skin surface
Tears
Fluid that washes and lubricates anterior surface of eyeball
Vitreous Humor
Transparent jelly-like substance inside eyeball
