Chapter: 3 Movement in & out of Cells

12.2 Sense organs

• The parts of an organism’s body that detect stimuli the receptors, may be specialized cells or just the endings of sensory neurons.
• In animals, the receptors are often part of a sense organ.
• A sense organ is a group of receptor cells that respond to a particular stimulus.
• Your eye, for example, is a sense organ, and contains receptor cells in the retina. These receptor cell are sensitive to light.

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The structure of the eye

• Figure 12.10 shows the internal structure of the eye.
• The part of the eye that contains the receptor cells is the retina.
• This is the part which is actually sensitive to light .
• The rest of the eye simply helps to protect the retina, or to focus, or to focus light onto it.

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