Download 1244509Health Nervous System 2012

What on earth is this?
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Composed of your:
◦ Brain
◦ Spinal Cord
◦ Nerves
***It is how we receive information
about EVERYTHING we do in life!!!!
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The nervous system is divided into two
different sections:
◦ Central Nervous System
◦ Peripheral Nervous System
 Brain
 Spinal
Cord
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If stretched out, the cerebral cortex would be
0.23 sq. m (2.5sq.ft), the area of a night
table.
The composition of the brain = 77-78%
water, 10-12% lipids, 8% protein, 1% carbs,
2% soluble organics, 1% inorganic salt.
The brain can stay alive for 4 to 6 minutes
without oxygen. After that cells begin die.
The slowest speed at which information
travels between neurons is 260 mph!!!
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The energy used by the brain is enough to
light a 25 watt bulb.
The weight of the average adult brain weights
about 3 pounds.
(In other words, how many thoughts does it
have per day?)
* Take a guess…………………………
 70,000 is the number of thoughts that
it is estimated the human brain produces on
an average day!!!!!
Men have slightly larger brains than women, BUT brain
size and brain weight do not reflect a person’s
intelligence.
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The command center for:
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Thinking
Processing
Actions
Ideas
Emotions
EVERYTHING!!!
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The brain’s best friend
◦ Relays messages from all parts of the body to the
brain…….
◦ THEN, it receives the message from the brain and
relays the brain’s message to muscles, glands, etc.
**** The spinal cord is like a bad gossiper, but in a
good way this time.
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Sensory: receive a message from outside
stimuli and send it to the spinal cord
Motor: carry out the message from the brain
to the muscles
*** Fire on desk example…
Involves all the nerves of the body.
 Carries messages to and from the body.
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Two Main Parts:
◦ Somatic System: actions that you can control (Ex:
looking, playing basketball, writing, etc.)
◦ Autonomic System: actions that you do NOT usually
control (Ex: heartbeat, breathing, digestion, etc.)
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Reflexes bypass going to the brain. Sensory/motor
neuron relationship all happens in the spinal cord.
Protects body from harm by causing our bodies to
respond quickly when threatened.
Ex: Pull hand away from hot stove.
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Through:
◦ Touch (Ex: Blindfolded….. Hand by stove)
◦ Hearing (Ex: Scratching on chalkboard, loud
screeching girl).
◦ Sight (Ex: Seeing a handsome boy or attractive
young lady).
◦ Taste (Ex: The worst bowl of homemade chili in
your life).
◦ Smell (Ex: You smell a BBQ in the summer time or
cinnamon buns baking in the kitchen at school).
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Parapalegic vs. Quadrapalegic
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Cerebrum
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Cerebellum
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Brain Stem
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Meninges
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Concussion