Human eyes are an amazing creation of nature, they allow you to explore the world around you, admire the sunset, look at a beautiful picture and just see the faces of your loved ones. The eyes give the opportunity to fully experience all the colors of life. Looking in the mirror, a person sees only a small part of his eyeball - the cornea and the white membrane. The main part of the organ of vision is hidden in the depths of the orbit.
Few people know, but the human eyeball does not have the shape of a regular sphere. More precisely, it consists of two components connected to each other. The anterior component of the eyeball is smaller than the posterior component. It is called the cornea. This part is attached to the white shell - the larger part of the eye. The average corneal size of an adult is approximately eight millimeters in diameter.
The cornea of the eye is connected to the white membrane with a special ring, it is called a border.
The size of the human eyeball
Each person has a unique appearance, the color of the eyes is also individual, however, the size of the eyeball in adults is almost the same. They can differ only by a couple of millimeters. Usually, the eyeball has a slightly elongated shape, that is, its dimensions horizontally are larger than vertically and are approximately 24 millimeters in diameter.
For a small, just-born man, everything is completely different, his eyeball is almost two times smaller than that of an adult. On average, the largest horizontal diameter is about sixteen millimeters. Surprisingly, the children's eyeball grows very quickly, by the age of three it reaches 22 millimeters in diameter. Already in the thirteenth year of a person's life, the eyeballs stop growing, because it is by this time that they reach their adult size.
The eyeball of an adult has a weight of about 7 grams and a volume of about 6 cubic centimeters.
The main structural elements of the human eyeball
The human eyeball has a rather complex structure, it consists of several membranes and a kind of eye nucleus. It is the transparent contents of the eyeball - the vitreous humor and the lens. The eyeball has three shells that surround the inner transparent part.
Outer shell - all the necessary muscles are attached to it in a special way. This shell serves to protect the eyeball and maintain its shape. The outer shell is divided into two components - the cornea and the sclera. The last component is quite dense, opaque and has a white tint.
The second shell of the eyeball is vascular. It is very important, it is in it that the main metabolic processes take place, this allows the human eye to feed. The iris and ciliary body adjoin the choroid of the eyeball. Cilia are designed to protect the eye from mechanical stress, excessive light and other possible negative environmental influences.
The third shell of the eyeball is the inner one, otherwise it is called the retina. It is thanks to this shell that all light and electrical impulses received by the eyeball are processed into a certain information flow, which is transmitted to the human brain. It is thanks to these complex processes that people are able to see and perceive the world around them.