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Tuesday, 10 February 2015

Structure Of An Eye

an-eye

The eye is a wonderful structure capable of generating the sense that the more we relate to the environment. Basically it is a kind of highly sophisticated camera so the aspect of vision as the ability to track an object with complex movements. Or objective lens of the camera is constituted by a set of tissues: cornea, lens, vitreous and aqueous humor. The diaphragm is located at the pupil center of the iris. The photographic film is represented by the retina.

CORNEA: 

The front part of the eye is a transparent dome, on which the contact lens is placed and Lasik is practiced.

CONJUNCTIVA: 

The transparent membrane that lines the front of the balloon excluding the cornea. Within it are tiny glands that produce tears and mucus that help lubricate and disinfect the eyeball.

CRYSTAL:

 The lens is precisely behind the iris, and its function is to achieve accurate focusing, which is known as accommodation. The shape of the lens is altered by a muscle which changes its curvature to focus on nearby objects and distant objects. When it loses its transparency, speaking of cataract.

IRIS:

 Behind the cornea is the iris: circular portion of pigmented tissue that gives color to the eye. The pupil, a circular is in the middle of the iris opening is enlarged and reduced to control the quantity of light entering the eye.

SCLERA:

 The sclera (or eyes) is the white fibrous outer layer that covers the eyeball. Its function is to protect the sensitive structures of the eye.

CHOROID:

 The choroid is the layer of blood vessels and lies between the retina and the sclera. It provides oxygen and nutrients to the retina. RETINA: The retina is a thin coat of multiple cell layers that is in the back of the eye. It is a membrane, light-harvesting antenna true. It functions as a screen on which the cornea and lens focus images. The macula, in the center of the retina, is the region that gives the vision of detail, allowing reading and color vision. There are two types of photoreceptor cells in the retina, cones and sticks, they transform images into nerve impulses sent to the brain. The cones require a relatively bright light (of day) for operation, but can detect many shades and nuances of color. By contrast, the rods require very low light (night), they allow viewing without colors, in black blue background.

AQUEOUS HUMOR:

 Is the fluid that fills the anterior part of the globe, between the cornea and iris. This is renewed permanently and drains into the bloodstream.

VITREO BODY:

 The vitreous is the transparent mass occupying the space between the lens and the retina. It consists of a gelatinous substance that maintains the shape of the eyeball.

The Education System In The Russia



The education system in the Russian Federation is a set of interacting structures, which include:

1. Continuity of educational programs at different levels and focus, federal state educational standards and federal government requirements.

Educational program determines the content of a certain level of education and orientation. In the Russian Federation implements educational programs, which are divided into:

General education (basic and advanced);

Professional (basic and advanced).

The basic general education program include:

Early childhood education;
Primary education;
General education;
Secondary (complete) general education.
The main professional programs include:

Initial vocational education;
Secondary vocational education;

Higher professional education (bachelor's degree programs, training programs and graduate programs);
Postgraduate education.
Taking into account the needs and abilities of the individual educational programs being developed in the following forms:

in an educational institution - in the form of full-time, part-time (evening), correspondence;
in the form of family education;
Self-education;

Externship.

A combination of different forms of education.

Lists of professions and occupations, the preparation of which a part-time (evening), part-time and in the form of external studies are not permitted in the competence of the Russian Federation established by the authorized Government of the Russian Federation, federal executive body (see. Resolution of the Government of the Russian Federation on primary, secondary and higher vocational education).

The use of distance learning technologies is the responsibility of the educational institution.

2. The network of educational institutions and scientific organizations implementing educational programs at different levels and focus, federal state educational standards and federal government requirements.

Educational institution is carrying out the educational process, that is, implementing one or more educational programs and (or) provide for the maintenance and education of students and pupils.

Educational institutions can be public (federal or under the jurisdiction of the Russian Federation), municipalities, non-governmental (private, public institutions and religious organizations (associations)).

An educational institution is a legal entity.