Sense organs: The eye Mrs. Newell Our sense organs • There are many stimuli in our surroundings that affect our behaviour. • These stimuli include light, temperature, sounds, gravity, touch and gravity among many others. • Our sense organs have receptors that detect these stimuli and send them to the CNS. We have five main sense organs: 1. Eyes 2. Nose 3. Skin 4. Ears 5. Mouth (tongue) Our sense organs Our sense organs The eye The eye • The eye receives light that it focuses on a layer of lightsensitive cells called the retina. • The retina contains cells of two types: rods and cones. • The rods only distinguish black and white light, while the cones are sensitive to colour (we’ll discuss the rods and cones in greater detail soon). • The retina coverts the light energy it receives and converts it to nerve impulses that are then sent to the brain. • The optic centre in the cerebral cortex of the brain produces the picture seen from the nerve impulses that were sent to it. The eye