User:Korkemxx/Cilia

Eyelashes (lat. Cilia) — hair, bordering the top and bottom of the eye incision in mammals.

General information
The function of eyelashes is to protect the eyes from dirt particles, dust, sand, also on small insects. They are located in 2-3 rows along the front edge of the free edge of the eyelids in humans. Behind them are the holes of the cluster glands, which are called meibomian; these glands are in a dense mass, like cartilage, connective tissue, which is inside the century. "Life expectancy"eyelashes in person consist is about 90 days.

Structure
Each eyelash consists of a rod and a root. The root is located under the skin and ends with an onion. Exactly bulb of eyelashes  responsible for its growth, which occurs due to the increased cell division of the bulb. The root and bulb are in the follicle, which is adjacent to 2-3 sebaceous glands. The bulb is adjacent to the skin papilla, with which the eyelash conducted fed and oxygen.

Color
The color of eyelashes is caused by the ratio of pigments of eumelanin and pheomelanin. Race accessory determines the thickness of eyelashes.

The life cycle is divided into 4 phases: active growth — 2-3 weeks, at rest 4-7 weeks, the other — the stage of rejection:


 * Anagen — the active phase of the hair follicle cover Catagen-a short transitional stage, at this time the follicle remains Telogen — follicle enters the resting stage, about 100 days.  Halogen — stage maturing new eyelashes.

The eyelash falls out when the root of the new eyelash ripens. Eyelashes are rising all time, but with age are beginning to thin, weaken and brighten.

Number
On the upper eyelid located from 70 to 150 lashes, they assign oily lubrication of the eyelids, on the lower, from 60 to 80. Upper lashes lower slightly longer, counting about 10 mm, while the lower length of about 7 mm.

Interesting fact
1. Before some operations on the eye, eyelashes are removed by the average medical personnel by means of scissors.

2. Eyelashes help to focus the image, by blocking the part of the light beams that would be superimposed on the retina, eroding the picture. The same effect occurs when looking at an object over the edge of the finger, although less noticeable due to the presence of only one thin strip of the image.

See. also

 * Ячмень (заболевание)