Uploaded by Jodykay Henry

Sense organs

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