explain the construction and the working of human eyes with labelling diagram
Answers
1. The eye ball is nearly spherical in shape . The front portion is more sharply curved and is covered by a transparent protective membrane called " cornea " . It is thin portion which is visible from outside .
2. Behind the cornea , there is place filled with a liquid called Aqueous humour and behind this a crystalline lens which is responsible for image formation .
3. Between the aqueous humour and the lens ,we have a muscular diaphragm called " iris " which has a small hole in it called pupil . iris is the coloured part that we see in an eye .
4.iris help in controlling the amount of light entering the eye through " pupil"
5. The ciliary muscles to which eye lens is attached helps the eye lens to change its focal length by changing the radii of curvature of the eye lens .
6 . The light that enters the eye forms an image on the retina .
7 . The distance between the lens and retina is 2.5 cm .
hope this will help u .
The outermost thin tough and curved transparent membrane over the front of the eye is called cornea.light enters the eye through cornea.it helps focus light onto retina
2 the centre of the iris is called pupil.the iris controls the width of the pupil which control the entry of light into the eye.in bright light the pupil becomes narrow and reduces the amount of light entering the eye
3 the lens is convex lens of variable thickness that focuses light to from a sharp image image on the retina
4 the retina is layer of light sensitive cells covering the inside of the back of the eye.when light falls on a retinal cell an electrical impulse from the cells is transmitted to the brain via optic nerve
5 the fluid between lens and retina is called aqueous humour.the fluid between lens and retina is called vitreous humour
