"Packets" of light waves are referred to as

Color is largely determined by the

Light bends as it passes through substances of different densities, a process known as

As your lens hardens through aging, you may have trouble with

Full dark adaptation, such as going from constant light to sudden darkness when turning out one's bedroom lights, takes about _____ minutes.

Thomas Young's theory of color vision

Cones are the special cells responsible for

In opponent-process theory, there are _____ primary colors.