EYE PHYSIOLOGY ANATOMY

EYE PHYSIOLOGY ANATOMY

The human vision is the eye. We can see and recognize an object that we see because of the cooperation between the eyes and the brain. Stimulation that occurs in the eye will be forwarded to the brain. Here the brain manages and translates the information received so as to produce a visual manifestation.

The eye consists of eyeballs located within the curve of the eye. In addition to the eyeball, in the curve of the eye there are also visual nerves and additional tools. Generally the eyeball is depicted as a sphere, but is actually rather oval. Eyes have special receptors that recognize changes in rays and colors. In addition there are muscles that serve as a mover of the eyeball, eye box (the cavity where the eye is located), eyelids and eyelashes. Viewed from the eye diagram, Not all living things have anatomical similarity to humans. Metaphorically, the human eye is often considered the "window of the soul".

The arrangement of the sense of sight in the outline consists of:

1.      Both eyes (the eye).

2.      The optic nerve, the nerve duct that connects the eye to the brain (the visual pathway).

3.      Center of vision in the brain (visural cortex).

Besides, there are aseanori organs that are important to protect and maintain the function of the eyes, ie eyelids, eyelashes, eyebrows and tear glands

A.    Understanding

The eye is part of the senses that have a limited function of receiving and preparing excitations to be passed on to the vision centers located within the brain. The eye is a visually sensitive visual apparatus (photo sensitive).
The human eyeball that is anterior to the anterior surface is only 1/6 (one-sixth) part only. While the remainder is protected in the orbita of the eye (the place of the eyeball)

B.     Eye Part

1.      Eyebrow

Eyebrows are fine hairs contained above the eyes. Eyebrows prevent water from swelling from the forehead to the eyes.

2.      Eyelashes

Eyelashes are fine hairs on the edge of the eyelid. Eyelashes serve to protect the eyes from foreign objects.

3.      Aquaeous Humor (Liquid Water)

Aquaeous humor or aqueous fluid is located behind the cornea. Its structure is similar to cell fluid, contains nutrients for the cornea and can perform gas diffusion with the outside air through the cornea, also serves to produce fluid in the eye and support the shape of the front pocket of the eyeball.

4.      Vitreous Humor

This clear body is located behind the lens. The form of transparent substances such as jelly (gelatin) is clear. This substance fills the eyeball and makes a rounded eyeball. The function of viteous humor is to pass light from the lens of the eye to the retina (mesh).

5.      Lakrima gland (tears)

The tear gland (lachrima) works to produce tears to moisten the eyes that keeps the moisture of the eyes, cleanses the eyes of the dust and kills the seeds of the disease that enter the eye.

6.      Eyelid

The eyelid consists of the upper petals and the lower petals. This section is to open and close your eyes. The eyelids serve to protect the front eyeball from foreign objects from the outside. These objects are for example dust, smoke, and scratches. The eyelid also serves to wipe the surface of the eyeball with a liquid. In addition, also to adjust the intensity of light entering the eye.

7.      Conjunctiva

The conjunctiva is a protective thin membrane (tissue layer) in the eye. The conjunctiva acts as a protective membrane in the eye.

8.      Optical nerve (eye nerve)

Eye nerve serves to continue the stimulation of light that has been received. Stimulation of light is transmitted central nervous system in the brain. Thus we can see an object. Optical nerve or eye nerve also serves to send visual information to the brain or forward information about the strength of light and color to the brain.

9.      Ligament Suspensor

The ligament suspension serves to keep the lens always in place.

C.     Anatomical Structure of the Eyes

Anatomically, the eyeballs can be divided into three layers from the inside out, namely:

1.      The Outermost Layer, consisting of:

a.       Sklera (white membrane)

Sklera is a strong connective tissue membrane, and is located on the outer layer of the white eye. Most sclera are built by fibrous tissue. In the sclera there is the cornea. Sklera works for the inner parts of the eyeball and to maintain eyeball rigidity as well to protect the eyeball from mechanical damage and allow attachment of muscles.

b.      Cornea (Clear membrane)

The cornea is the clear membrane that lines the anterior part of the eyeball. The cornea is also the entrance of light to the eye by placing it on the retina. The outer layer of the cornea is covered by a continuous epithelial layer with an epidermis called a conjunctiva. The cornea serves to allow light to pass and reflect light.

2.      Vascular layer, consisting of:

a.       Koroid

The coroid is a thin, dark membrane layer. This layer contains many pigments and blood vessels that contain many blood vessels that deliver nutrients to the retina, also coating the inner surface of the sclera. At the front of the choroid, behind the corneater can be a structure called Iris. The coroid serves to absorb light and protect the reflection of light in the eye.

b.      Iris

Iris is a diaphragm located between the cornea and the eye. On the iris there are two smooth muscle devices that are circular and radial. Iris serves to regulate the amount of light entering the eye, by way of raising or shrinking the pupil, the hole located in the center of the iris.

When the eye accomodates to see a close object or a bright light the circular muscles contract so the pupil shrinks, and vice versa.

Iris also affects the eye color of a person, which is related to the amount and nature of the pigment contained therein.

c.       Lens

The lens of the eye serves to refract the incoming light and focuses the light on the retina. The lens is directly behind the iris and depends on the suspensory ligament. The shape of the lens may vary, regulated by the ciliary muscles. The space between the lens of the eye and the retina is called the venous space, containing more viscous fluid (humor viterus), which along with the humus acueus plays a role in maintaining the shape of the eyeball.

Retina
The retina is a light-sensitive vertebrate eye, the deepest layer of the eyeball. This section serves to receive light, converting it into nerve impulses and delivering impulses to the optic nerve (II). The retina is composed of layers of neural tissue (the inside is the visual part) and the pigmented layer (the outside is a non-visual part).