When light enters the human eye, it is transferred to the optic nerve to help us see the object at which we are looking. The eye is made out of several components, including cells, fluids, blood vessels, membranes, tissues and nerves.
The retina has over 130 million cells that respond specifically to light, including millions of rods and cones (which are specialized photoreceptor cells) that convert light into what we see.
The eye contains the aqueous and vitreous humors. The aqueous humor is defined as the clear liquid in the front of the eye that lies between the cornea and the iris. The vitreous humor is a gel that helps the eye keep it's shape.
The eye contains several million different kinds of nerve endings, such as the macula. The macula lies inside the retina and contains the nerve endings called photoreceptors.
The human eye also consists of tissues, such as the retinal pigment epithelium (RPE). According to WebMD, the RPE is a layer of dark tissue beneath the photoreceptors.
Blood vessels are intertwined in the eye and feed nutrients to the nerve cells.
Membranes and Muscles
The sclera is a tough membrane that protects all the inner parts of the eye. It’s what people know as the “whites of the eyes.” Another membrane is the choroid, which is a thin membrane on which the retina sits. The eye also contains several kinds of muscles, including the ciliary muscle and orbital muscles.