The macula has the highest concentration of cones in the eye. Most of the detailed vision comes through the work of the macula.
The eye gives vision to the body and is a combination of nerves, cells and fluids. The optic nerve is the eye's largest sensory nerve and it carries electrical impulses to the eye. The choroid is the largest blood vessel responsible for carrying blood to the retina.
The following parts of the eye are visible when looking at it:
- Iris: the colored tissue of the eye; it controls the amount of light that enters
- Pupil: the hole in the iris that allows light to enter
- Sclera: the white part of the eye
The eye uses the cornea to refract light and it accounts for most of the eye's ability to focus. The lens provides the remaining focusing power as it directs light to the retina, which is the layer of light-sensitive cells at the back of the eye. The retina is responsible for converting light into electrochemical signals that go to the brain. The retina contains receptor cells called rods and cones, which are necessary for night vision, acuity and color perception.
In the center of the retina is a small depression called the fovea centralis, or macula. The macula contains the highest concentration of cones and it is where the eye has the sharpest vision.