Chapter: 3 Movement in & out of Cells

Rods and cones

• The closer together the receptor cells are, the clearer the image the brain can produce.
• The part of the retina where the receptor cells are packed most closely together is called the fovea.
• This is the part of the retina where light is focused when you look straight at an object.
• We have two kinds of receptor cells in the retina.
• Rods are sensitive to quite dim light, but they do not respond to color.
• Cones are able to distinguish between the different color of light, but they only function when the light is quite bright. We have three different kinds of cones, sensitive to red , green and blue light.

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