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370707510 body parts

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PARTS OF THE EAR
The human ear functions in such a way that sound
waves travel from the outer ear to the middle ear,
which are then transmitted to the inner ear in the
form of compressional waves. In the inner ear, the
compressional waves are converted into electric
impulses that are perceived by the brain. This way,
we can hear and differentiate various sound types.
Outer Ear
The outer ear or external ear is the visible portion of
the ear, which serves as a protective organ for the
eardrum. It collects and guides sound waves into
the middle ear. The outer ear consists of the Ear
Flap and the Ear Canal.
Ear Flap (Pinna) - The sound waves enter the ear
via the ear flap or pinna.
Ear Canal (Meatus) - The ear canal is about 2 cm
in length. It amplifies the sound waves and
channelizes them to the middle ear. Sweat glands
are present in this canal, which secrete earwax.
Middle Ear
The middle ear, located between the outer ear and
the inner ear, perceives sound waves from the
outer ear in the form of pressure waves. The middle
ear is an air-filled cavity and consists of the
Eardrum, Hammer, Anvil, and Stirrup.
Eardrum (Tympanic membrane) - The eardrum is a
thin membrane that acts as a partition between the
outer ear and the middle ear. It vibrates as soon as
it receives sound waves, and transforms the sound
energy into mechanical energy.
Hammer (Malleus) - It is a tiny bone, located next to
the eardrum. Since it lies adjacent to the eardrum,
the vibrations from the eardrum cause the hammer
to vibrate.
Anvil (Incus) - Anvil is another tiny bone next to
hammer; it vibrates in response to the vibration of
hammer.
Stirrup (Stapes) - Similar to hammer and anvil,
stirrup is a tiny bone in the middle ear. Eventually, it
also vibrates and passes the compressional waves
to the inner ear.
Inner Ear
The inner ear or Labyrinth, as the name suggests,
is the innermost portion of the ear. It is filled with a
water-like substance and comprises both hearing
and balancing organs. The inner ear comprises the
Cochlea, Semicircular Canals, and the Auditory
Nerve.
Cochlea - The cochlea or the spiral tube is a rolled
structure that can stretch to about 3 cm. The
membrane lining of cochlea consists of numerous
nerve cells. These hairlike nerve cells respond
differently to various frequencies of vibrations,
which ultimately lead to generation of electrical
impulses.
Semicircular Canals - These are fluid-filled loops,
attached to the cochlea and help in maintaining the
balance.
Auditory Nerve - The electrical impulses, generated
by the nerve cells, are then passed to the brain.
This way, the different parts of the human ear
perform specific functions that contribute to the
overall functioning of the ear. Any damage and/or
disorder in the ear parts may lead to ear problems
and hearing loss (deafness).

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PARTS OF THE EYE
Sclera: The sclera is the white part of the eye that
surrounds the cornea. It is made up of fibrous
tissues, and provides protection to the inner parts
of the eye. This is the tissue that is commonly
called the white of the eye.
Cornea: The cornea is the transparent tissue at the
front of the eyes through which light coming from
an object enters the eye. It also helps in focusing
the light on the retina.
Aqueous Humor: It is a clear transparent fluid that
fills the space between the cornea and the eye
lens. It also supplies nutrients and oxygen to these
parts.
Iris: The iris is a ring of muscles in the central part
of the eye, that is helpful in regulating the amount
of light entering the eye by controlling the size of
the pupil.
Pupil: This is an opening in the center of the iris
through which light passes and falls on the eye
lens. Its size is controlled by the iris.
Eye Lens: The lens of the eye is situated directly
behind the pupil. It helps in focusing the light on the
retina. The eye lens is capable of changing its
shape so as to enable us to see objects near and
far.
Ciliary Muscles: This is a ring-shaped tissue that
holds and controls the movement of the eye lens,
and therefore, helps in controlling the shape of the
lens.
Vitreous Humor: It acts as a filler and covers the
space between the eye lens and retina. It also
provides protection to the lens. It makes up for
about two-thirds of the total volume of the eye, and
is composed mainly of water.
Retina: It is a membrane responsible for converting
the light falling on it into electrical impulses that can
be sent to the brain. The retina contains light-
sensitive photoreceptor cells called rods and cones.
The rods help in black and white vision and for
seeing in dim light, while the cones help in daytime
and color vision.
Optic Nerve: It is a bundle of nerve fibers that serve
as a cable that connects the eye to the brain. This
optic nerve helps in transmitting signals from the
retina to the visual center of the brain.
Yellow Spot or Macula: Situated at the center of the
retina, this yellow spot helps in absorbing excess
light that enters the eye. The macula is responsible
for our reading vision, and helping us to see objects
right in front of us.
Eyelids: The eyelids help in the protection and
lubrication of our eyes. They also help in controlling
the amount of light falling onto our eyes.
Muscles of the Eye: The eyeball is held in its place
by the help of several eye muscles. The eye
muscles are responsible for the up and down, as
well as the left and right movement of the eye.

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PARTS OF THE EAR The human ear functions in such a way that sound waves travel from the outer ear to the middle ear, which are then transmitted to the inner ear in the form of compressional waves. In the inner ear, the compressional waves are converted into electric impulses that are perceived by the brain. This way, we can hear and differentiate various sound types. Outer Ear The outer ear or external ear is the visible portion of the ear, which serves as a protective organ for the eardrum. It collects and guides sound waves into the middle ear. The outer ear consists of the Ear Flap and the Ear Canal. Ear Flap (Pinna) - The sound waves enter the ear via the ear flap or pinna. Ear Canal (Meatus) - The ear canal is about 2 cm in length. It amplifies the sound waves and channelizes them to the middle ear. Sweat glands are present in this canal, which secrete earwax. Middle Ear The middle ear, located between the outer ear and the inner ear, perceives sound waves from the outer ear in the form of pressure waves. The middle ear is an air-filled cavity and consists of the Eardrum, Hammer, Anvil, and Stirrup. Eardrum (Tympanic membrane) - The eardrum is a thin membrane that acts as a partition between the outer ear and the middle ear. It vibrates as soon as it receives sound waves, and transforms the sound energy into mechanical energy. Hammer (Malleus) - It is a tiny bone, located next to the eardrum. Since it lies adjacent to the eardrum, the vibrations from the eardrum caus ...
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