Eye Anatomy Flashcards
Aqueous Humor
A clear fluid that helps the cornea keep its
rounded shape.
Optic Nerve
The bundle of nerve fibers that carry information
from the retina to the brain.
Blind Spot
The place where all nerves from the retina join to
form the optic nerve. Each eye has a blind spot
where there are no light-sensitive cells.
Pupil
The pupil is the dark circle in the center of your
iris. It’s a hole that lets light into the inner eye. Your
pupil is round. A cow’s pupil is oval.
Cones
One kind of light-sensitive cell in the retina. Cones
give you color vision in bright light.
Retina
The layer of light-sensitive cells at the back of the
eye. The retina detects images focused by the
cornea and the lens. The retina is connected to the
brain by the optic nerve.
Cornea
A tough, clear covering over the iris and the pupil
that helps protect the eye. Light bends as it passes
through the cornea. The cornea begins bending
light to make an image; the lens finishes the job.
Rods
One kind of light-sensitive cell in the retina. Rods
respond in dim light.
Iris
A muscle that controls how much light enters the
eye. It is suspended between the cornea and the
lens. A cow’s iris is brown. Human irises come in
many colors, including brown, blue, green, and
gray.
Sclera
The thick, tough, white outer covering of the
eyeball.
Lens
A clear, flexible structure that makes an image on
the eye’s retina. The lens is flexible so that it can
change shape, focusing on objects that are close
up and objects that are far away.
Tapetum
The colorful, shiny material located behind the
retina. Found in animals with good night vision,
the tapetum reflects light back through the retina.
Vitreous Humor
The thick, clear jelly that helps give the eyeball its
shape.
Myelin
The fatty layer that surrounds each nerve fiber.
