The sense of sight

The sense of sight
The sense of sight allows us to perceive the form, distances, position, size and color of all the objects and beings who surround us.
The eyes are the receiving organs of the sight, they have the function to receive the luminous stimuli that we find in the ambience.
They are located in the cavities called orbit, that protect them from the shakes and exterior shocks. The eyebrows, the eyelashes and the eyelids complement its protectión.
Severa mani parts
1) The iris. It is the colored part of the eye . It regulates the light entry increasing or diminishing its size as the intensity of the same one. 
2) The pupil. It is the central orifice of the iris. It dilates or contracts according to the quantity of existing light.
3) The crystalline one . It is the part that focuses the light bundle in the retina. It has form of biconvex lens.
4)  The  cornea. It is one of the external parts of the eye. It protects the crystalline one and the iris allowing the step of the light.
5) The retina. It is the part of the eye sensitive to the light. It is composed by the cones and the canes. Its function is to give information about the clearness, color and sheen.
6) The sclerotic. It is the most external membrane that protects and gives form to the eye. It is the area that we know as "the white of the eye ".
7) Optical nerve. He leads the nervous impulses of the cones and canes of the retina towards the brain. This allows the formation of the images in our head.
8) The watery humor. It is a colorless liquid located between the cornea and the crystalline one. Its function is to lubricate and to feed the eye by means of the proteins  that it contains.
9) The glassy humor. It is a gelatinous and transparent substance centained inside the globule ocular and been in charge to exercise pressure on him.
It takes care of your eyes reading with the suitable light and without rubbing them with the dirty hands.
Fun fact

Optical ilusion...

... and curiosities


Blue and grey or pink and white?