Rod cells, or rods are photoreceptor cells in the retina of the eye that can function in less intense light. Since they are more light-sensitive, rods are responsible for night vision, but also allow for the perception of color. Named for their cylindrical shape, rods are concentrated at the outer edges of the retina and are used in peripheral vision. There are about 120 million rod cells in the human retina.

See Human Eye.
See Cones.

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