Blindness.

Did you see blind people? I hypothesise you did. Did you compute how they live? Do you know what problems they sustain? While I made this investigation I understood much much about blindness. This is a result of my investigation. What authors blindness? The eye and a camera have a lot in common. They some(prenominal) have compound lenses. The cornea and the lens ar in buck of foc hold light as it enters the eye. The lens is adjustable to bring habitation the bacon viewing of both foldly and distant objects. The iris, just alike the iris in a camera, controls the amount of light that enters the eye. It opens and closes to promote the sensitive retina from to much light. The retina covers the back of the eye. It contains millions of photo-receptor cells. These cells react to the presence and posture of light and send impulses to the brain through the centre nerve. These impulses be converted into sight by the brain. thither are many another(prenominal) things, which cause blindness. fewtimes people are born blind, their blindness or visual impairment is congenital (meaning born with). But close to blind people become blind later on. nearly people become blind after accidents. Wearing preservative eyeglasses or goggles during activities such as using power tools, playing racquetball, or working with chemicals can patron prevent such accidents.

Glaucoma, cataracts, and diabetic retinopathy are the three more or less common causes of blindness today. Glaucoma is a illness that causes increased silver-tongued pressure inside the eye. A liquified called the aqueous wag fills the gap between the lens and cor! nea. There are valves in this part of the eye that regulate the eyes native pressure. The increased pressure, from this condition, destroys the optic nerve. It can cause blindness and in any case tunnel vision. If you close one eye and look... If you want to beat a dear essay, order it on our website: OrderCustomPaper.com

If you want to get a full essay, visit our page: write my paper