Gives us information about shape, color, distance. Light is the environmental stimulus and vision is the psychological aspect.
Cornea - clear membrane, curved surface that helps bend light as it enters the eye
Iris - ring of muscles that contracts and dilates to control the light entering the eye. Sometimes changes in emotional state. Angry - contracts Happy - dilates
Pupil - opening in the center of iris. It is a hole in the center of the eye
Lens - changes shape to focus on objects that are close/far completes the bending process for the eye
Retina - responds to the light and converts it into patterns of action potential.
The image on the retina is then transformed into electrical signals in a process known as transduction. This allows the visual messages to be transmitted to the brain to be interpreted.