Basic Eye Anatomy and Vision Terms

Translucent

• Allows some light to pass through

• Blocks all light completely

• Reflects all light

• Absorbs all light without passing through

Cone Cells

• Cells in the retina responsible for color

• Cells in the retina responsible for night vision

• Cells in the retina that detect motion

• Cells in the retina that provide structural support

Retina

• The light-sensitive layer of tissue at the back of the inner eye

• The colored part of the eye that controls the size of the pupil

• The transparent front part of the eye that covers the iris and pupil

• The nerve that transmits visual information from the eye to the brain

Rod Cells

• Cells in the retina responsible for vision in low light conditions.

• Cells in the retina responsible for color vision.

• Cells in the retina that detect motion.

• Cells in the retina that provide sharp central vision.

Refraction

• The bending of light

• The reflection of sound

• The absorption of heat

• The scattering of particles

Photons

• Particles of light that are the basic units of light and all other forms of electromagnetic radiation.

• Waves that travel through a vacuum and carry energy.

• Atoms that emit light when heated to high temperatures.

• Electrons that are released from atoms when they absorb energy.

Optic Nerve

• The nerve that transmits visual information from the retina to the brain.

• The nerve responsible for hearing and balance.

• The nerve that controls facial expressions.

• The nerve that regulates heart rate.

Opaque

• Allowing light to pass through

• Not allowing light to pass through; not transparent or translucent.

• Partially allowing light to pass through

• Reflecting light without transmission

Pupil

• The colored part of the eye that surrounds the pupil.

• The opening in the center of the iris that allows light to enter the eye.

• The transparent layer covering the front of the eye.

• The part of the eye responsible for sharp vision.

Transparent

• Allows all light to pass through

• Blocks all light

• Reflects some light and absorbs others

• Scatters light in different directions