The Eye
There are five senses in the human body: the sense of sight or vision. The purpose of invention plays an essential part in our lives because we can see the colorful world through an understanding of sight.
The Structure of Eye
The shape of Eye is sprical. The outer whitish part of Eye is called sclera which is opic.
The dark part of sclera is called Cornea. The colored part of the Cornea is iring, and the middle part of the Cornea is called pupil which looks like a hole.
The eye lens is an essential part of the Eye. The eye lens is convex in shape and is connected through ciliary muscle.
Inner side of the Eye is made of nervous tissues; retina is also present in inner side of the Eye. Retina is the most delighted part of the Eye. Retina has two types of cells rods and cones. Cone cells are responsible for color and identification of objects and rod cells for night and peripheral vision.
Function of Eye
The light enters into the Eye through Cornea. The Iris control the amount of light with the help of pupil.Pupil controls the amount of light that enters the Eye.
The lens which is present behind the Iris changes its shape and focuses the light on the retina. The eye lens refract the light and with the help cillary muscles it changes its focus.For nearer object lens become thick and for distanced objects it become thin.After passing from the lens, the light is focused on the retina.
A small area in retina which is called macula is responsible for the sharp and clear vision. The rods and cones cells of retina convert light rays into nerve impulses. Then the light in the form of nerve impulses pases through optic nerve into the brain.
The Ear
The ear is also one of the most important sense from all 5 senses.we hear all types of sounds through our ears.
The Structure of the ear
The outer soft cartilaginous part of the ear is called the pinna, which collects all types of sound waves from the surrounding environment.
The second part is ouditary canal through which all sound waves are passesed.
Next comes the eardrum, which is a transparent layer and is sensitive tovibration. Eardrum separate external ear from internal part.
The middle part of the brain has three small bones, malleus incus, and stapes collectively called osicls.
The iner part of ear has three sami circular rings which helps in maintaining the balance of the body, and a snail-like Structure called the cochlea.
Then comese the auditory nerver which carry sound waves from ear to brain.
Function of ear
Pinna of the ear collects all sound waves from surrounding and transfers them through the auditory canal towards the eardrum.
The eardrum is sensitive to vibration. When the sound waves hit the eardrum, it activates three bones( mulas incus and stapes)osicls.
Osicls pass these sound waves into inner ear.The osicles also amplify the sound waves because the inner ear has liquid and for vibration of the high liquid pressure is required, and osicles can increase the pressure.
The sound waves after the middle ear enter into the inner the three sami circular rings present in the internal ear transfer the sound waves to the cochlea.
Insid Cochlea special cells are present, which convert sound waves into an electrical signal. The sounds waves in the form of electrical signals are conveyed to the brain through the auditory nerve.
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