Structure and Function of Human Eye
Shape:-
Eye is small organ. It is spherical in shape.
Size:
The eye is 2.4cm in diameter.
Location:
Each eye is present in bony socket called orbit. Socket also contains muscle that move eye ball.
Eye Lids:
Eyelids are present upper and lower of each eye.
Parts of Eye:
- i) The outer most layer of eyeball is whitish in colour and form cornea.
- ii) The second layer of eyeball is called choroids.
iii) Behind cornea choroids bends inwards to form Iris having circular opening called pupil.
- iv) Behind pupil a biconvex lens is present.
- v) The innermost layer of eye is called retina.
Sensory Cells:
The sensory cells of eye have two types:
- a) Rods b) Cones.
These cells help in the formation of image on retina above the point of entry of optic nerve called blind spot.
Tear Glands:
Tear glands are also present in the socket. The secretion of these glands washes the eyes.
Image Formation on retina:
- i) The light rays coming from object focuses from retina.
- ii) They rays are focused in a special spot called fovea centralis.
iii) This spot produce sharp image.
- iv) Lens plays important role by changing its convexity to produce enough refraction.
- v) AI last it bring the image into focus and form a clear image on retina
First, to teach your child to recognize books, read to him from a very early stage of development.
Reading fairy tales, stories will make it clear to the child that reading allows him to spend more time with mom and dad. In this regard, when you read, the child will have an association with security. After all, when the reading process takes place, you are there and can protect it. You can chat with young parents on the forum and find out what books the children love, download them to your Kindle and read before bed. When the child begins to play with toys on his own, give him books that he can not only touch, but also chew and tear. Thus, he will associate them with fun activities.