Page 46 - (DK) How to be a GENIUS?

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Your skin is the largest organ in your body. It has
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many functions, including acting as a protective
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barrier against infection, but it also provides you
with vital information about your environment.
It does this by using millions of sensory receptor
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cells that detect different types of stimuli—from
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the most delicate tap to the sharp shock of pain.
Free nerve endings
Sense touch, pressure,
pain, and temmperature
Thalamus

Sensitive skin
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Human skin has at least six types of
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sensory receptors. Some are branched
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n nerve endings, while others are nerve fibers
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that end in tiny disks or cappsules that
es that
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detect different types of pressure,
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vibration, stretching, temperature
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change, and physical damage. Some
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nerve endings are wrapped around the
roots of hairs and sense their response
to touch and air movement.
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Merkel’s disk
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Responds to light
touch and pressure
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There are around Hai ir root sensors
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1 18 million skin sensors D Detect hair movement
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a l to e t h er , c o n s t a n t y
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altogether, constantly
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et
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sending information
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to the brain. . Fingertip control
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Sign al network Some parts of your skin are much
more sensitive than others. If
Sensory y signals from the skin are sent through
something touches your leg,
nching nerves of the peripheral nervous
the bran you can certainly feel it, but the
system to the spinal cord and then to the By contrast, your fingertips are
sensation is not very precise.
thalamu s. The thalamus passes them on to the highly sensitive, giving you the
sensory cortex, which is located in the
somatic s sense of touch that allows you
brain. Th e thalamus acts as a relay station, as it to feel textures and, in the case
does for r all sensory information except smell. of blind people, to read Braille.
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