The Nervous System

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The Nervous System
MTTC- the links to the United Streaming videos
wont work since the videos are stored on the
body systems disk.
Lisa Rogers July 07
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Your spinal cord can be divided into four
sections shown in green, blue, pink and
turquoise. Nerves emerging from these sections
serve different parts of your body.
Introduction
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Parts of the Nervous System

• Brain
• Main control center of body
• Directs and coordinates all body processes,
  thoughts and behaviors

• Spinal Cord
• Connects brain to peripheral nervous system
• Impulses pass through cord when brain sends
  messages to body
• Two types of nerves
• Motor
• Sensory

Inside the Brain Interactive Tour
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Parts of the Nervous System

• Nerves
• 31 pairs of nerves branch out to both sides of
  the body
• Carry messages to and from other nerves
• Controls movement

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Parts of the Brain

• Cerebrum
• Largest part of brain
• Controls all conscious body movements
• Interprets impulse from sense organs
• 2 halves
• Left speech, math logic
• Right music, art, emotions

Closer look at the brain
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Parts of the Brain

• Cerebellum
• Adjusts impulses of motor neurons
• Controls fine motor movements

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Parts of the Brain

• Brainstem
• Connects the spinal cord to the rest of the brain
• Coordinates vital functions breathing, heart
  rate, blood pressure, sleep
• Has three parts
• Midbrain
• Pons
• medulla

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Neurons

• Neuron
• Specialized to transmit nerve impulses

• Cell body
• Main part of a neuron (nerve cell)

Narrated Neurons
All about Neurons
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Neurons

• Dendrite
• Transmits nerve impulses from other cells or
  sensory systems

• Axons
• Transmit nerve impulses away from cell body

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Neurons

• Schwann Cells
• Supporting cells associated with axon
• Form a myelin sheath around vertebrate neurons

• Myelin sheath
• Protective coat on neurons
• These break down when someone has Multiple
  Sclerosis

Build a Neuron
Parts of the Neuron quiz
Color a Neuron
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Neurons

• Nodes of Ranvier
• Interrupts myelin sheath where axon is indirect
  contact with surrounding intercellular fluid

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Fun Facts

• Average number of neurons in the human brain 100
  billionAverage number of neurons in an octopus
  brain 300 billion
• There are more nerve cells in the human brain
  than there are stars in the Milky Way.
• If we lined up all the neurons in our body they
  would stretch for 600 miles!!!

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Questions

• Why Do I Shiver When I Am Cold?     The body
  always works at keeping its temperature at a
  constant level. You probably know that this
  temperature is 98.6 degrees F. At this
  temperature the cells of the body work
  best.     In the hypothalamus (a special section
  of the brain) there is an area that controls
  heat, thirst and other body functions. When you
  get too hot or too cold, this center alerts the
  rest of the body. It sends messages that either
  cool you off or warm you up. On a very cold day
  you may start shivering. The heat control center
  in the hypothalamus has sent a message to your
  muscles to move very rapidly. Work is being done
  by the muscles and heat is given off. When
  muscles shiver, two to four times more heat can
  be given off. The extra heat helps to keep you
  warm

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Questions

• Why Do I Get A Fever When I Am Sick?     A
  common cause of fever is infection. It seems that
  when you have an infection many factors activate
  the area of the brain called the hypothalamus.
  One important factor is the material produced at
  the site of the infection. These substances
  travel through the bloodstream to the brain and
  alert the body's heat control center. The center
  responds by making the cells work faster. The
  increased work raises the temperature of the body
  and you have a fever. The fast-working cells are
  able to make more antibodies to fight the
  infection. The fever also makes the body too hot
  an environment for bacteria to live in.
  Unfortunately, the fever also makes you feel
  sick.

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• Inner Body
• Comparing brain sizes
• Simple experiments
• Split brain interactive
• Photographs of neurons
• Senses challenge
• Sheep brain dissection
• Interacts with other systems
• Brain games
• More brain games

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• Lots more info