Peripheral Nervous System

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Section 12.3

• Peripheral Nervous System

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Peripheral Nervous System

• Nerves that carry information to and from the
  brain
• Several types of nerves
• 1. sensory nerves
• 2. motor nerves
• 3. association nerves

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Sensory Nerves

• Nerves that receive stimuli and carry the
  messages to CNS

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Motor Nerves

• Carry messages back from the CNS to muscles and
  glands

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Association Nerves

• Connect sensory and motor nerves

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Receptors

• Nerve cells that receive information
• Different types for different things
• Ex temp., pain, taste, smell, color

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Peripheral Nervous System

• 2 parts
• 1. somatic nervous system
• 2. autonomic nervous system

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Somatic Nervous System

• Motor nerves that carry signals to skeletal
  muscles and sensory nerves
• Conscious control

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Autonomic Nervous System

• Controls smooth muscle that lines internal organs
• Also controls glands and heart rate
• Automatic control

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Reflex Action

• Involuntary action
• Do without thinking about it
• Ex
• Pulling hand back from hot pan
• Baby pulling leg when given shot
• Jerking leg when stepping on a tack

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Protection

• Signal bypasses brain
• Built in protection If signal had to go all the
  way to the brain, it would take longer.
• You would keep your hand on the hot pan longer
  and would be burned