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Eyes
Eyes
Eyes : The Organs of Sight: The Organs of Sight: The Organs of Sight
The eyes are the organs of sight. The eyelids and the eyelashes protect them
from dust and dirt. The black spot in the centre of eye is called the pupil . The
coloured circle is called the iris . The amount of light that passes through the
pupil is controlled by the iris. The pigmentation of the iris gives the colour to

eyes. The optic nerve carries messages from the eye to the brain.

Iris Retina Care for the eyes :

Cornea w Do not read in dim or very bright light.
w Do not rub your eyes with dirty hands.
Conjunctiva
w Clean your eyes regularly.
Pupil
w Do not read in a moving car or bus.
Lens Optic nerve w Do not watch television for long and sit

Structure of an Eye at least six feet away from it.

Ears
Ears
Ears : The Organs of Hearing: The Organs of Hearing: The Organs of Hearing
The ears are the organs of hearing. They also help us to keep our body
balanced.
An ear has three main parts, that are external ear , middle ear and internal ear .

The external ear consists of the pinna and the auditory canal . The sound

waves, collected by the pinna, travel through the auditory canal and strike the
eardrum. The eardrum is connected to the middle ear which has three tiny

bones. These bones carry the sound waves to the cochlea of the internal ear.

From the cochlea, the sound waves are carried to the brain by the auditory
nerve.
Skull bone Semicircular
Care for the ears : canals
Pinna Cochlea
w Never use a matchstick or hairpin to
Cartilage
clean your ears.
Ear canal
w You must consult a doctor in case of an

Eardrum
earache.
w Never hear loud music. Eustachian tube

Fact File
Fact FileFact FileFact FileFact FileFact File Structure of an Ear
Fact File
Fact FileFact FileFact FileFact FileFact File
The weight of the brain in average adult males is 1375 grams while in
females, it is 1275 grams.

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