Anatomy: Eye and Vision
Which portion of the retina contains a concentration of cones?
Fovea centralis
What term refers to the ability to focus on close objects?
accommodation
What part of the eye has the greatest visual acuity?
fovea centralis
Which of these is associated with rods?
vision in dim light
Which disorder of the eye results from increased pressure due to a buildup of aqueous humor?
Glaucoma
What separates the aqueous humor in the anterior segment from the vitreous humor in the posterior segment of the eye?
Lens
Where are photoreceptors cells located within the eye?
Neural layer of the retina
Which statement regarding the function of the pupil is correct?
The pupil regulates the amount of light entering the eye, so we can see as clearly as possible.
An astigmatism results from unequal curvatures of the cornea or lens.
True
The ciliary body is a smooth muscle structure to which the lens is attached.
True
The normal resting eye is generally "set" for distant vision.
True
The pupil is the circular opening in the iris through which light passes.
True
We cannot see images formed on the optic disc (blind spot).
True
Which of the following structures refract light before it hits the retina?
cornea, humors, and lens
Which of these is located in the superior-lateral region of the orbit?
lacrimal gland
Which of these structures is part of the system that produces and drains tears?
lacrimal gland
The biconvex structure that focuses light on the retina is the ________.
lens
What part of the eye is affected by cataracts?
lens
The inability to see distant objects is termed "nearsighted" or ________.
myopia
At what point do some axons leave the optic nerve and cross to the opposite side of the brain?
optic chiasma
The function of the choroid layer of the eye is to ________.
prevent light from scattering inside the eye
Which layer of the eye contains photoreceptors known as rods and cones?
retina
Which of these is part of the sensory layer of the eye?
retina
What is the orientation of images formed on the retina?
upside down and reversed left to right
The gel-like substance that reinforces the eyeball and prevents it from collapsing inward is the ________.
vitreous humor
What condition results from an abnormally high pressure inside the eye?
glaucoma
The transparent portion of the fibrous layer of the eye is the ________.
cornea
Tears from the lacrimal gland travel across the eye and drain first into the ________.
lacrimal canaliculi
Fibers from the medial side of each eye cross over to the opposite side of the brain at the ________.
optic chiasma
Where do the axons of ganglion cells leave the eyeball?
optic disc
What is the most common type of color blindness?
red and green
What type of photoreceptor cell allows us to see gray tones in dim light, and provides our peripheral vision?
rods
The fibrous covering of the eye consists of the white outer layer known as the ________, and a transparent portion known as the ________.
sclera and cornea
What layer of the eyeball contains both pigment to absorb stray light rays and muscle to control the lens?
choroid
Which of the following is a sex-linked condition that more often affects males?
color blindness
The membrane that covers the outer surface of the eye and lines the eyelids is the ________.
conjunctiva