The amplitude of electromagnetic waves determines the ________ of light.

• absolute threshold
• brightness
• hue
• difference threshold

The adjustable opening in the center of the eye is the

• fovea.
• iris.
•  cornea. 
• pupil.

Dilation and constriction of the pupil are controlled by the

• optic nerve.
• lens. 
• retina.
•  iris.

Accommodation refers to the

• system for sensing the position and movement of muscles, tendons, and joints. 
• quivering eye movements that enable the retina to detect continuous stimulation
• process by which stimulus energies are changed into neural messages.
•  process by which the lens changes shape to focus images on the retina.

The light-sensitive inner surface of the eye, containing the rods and cones, is the

•  fovea.
• optic nerve.
• cornea.
•  retina.

Which of the following is the correct order of structures light passes through in the eye?

• a. lens, cornea, pupil, retina, iris
• retina, lens, cornea, rods, cones 
• cornea, iris, pupil, lens, retina
•  pupil, optic nerve, retina, lens, rods

The axons of ganglion cells converge to form

• the basilar membrane.
• bipolar cells.
• the auditory nerve.
•  the optic nerve.

Compared with rods, cones are

•  more sensitive to dim light and more sensitive to fine detail. 
•  less sensitive to dim light and less sensitive to fine detail.
• more sensitive to dim light and less sensitive to fine detail.
• less sensitive to dim light and more sensitive to fine detail.

The area of the retina where the optic nerve leaves the eye is called the

• blind spot.
•  pupil.
•  visual cortex.
• cornea.

The direct link between a single cone and a single ________ preserves the fine details in the cone's message.

• rod
• ganglion cell
•  blind spot
• bipolar cell