Download The Nervous System

Chapter 4
Section 1
 Functions
• Gather and interpret information
• Respond to information as needed
 Central
Nervous System (CNS)
• Brain
• Spinal Cord
 Peripheral
Nervous System (PNS)
• All other parts of the nervous system
• Nerves connecting body to CNS
 Neuron: a
nerve cell, specialized to
transfer messages
• Can be very short or quite long
 Impulse: Message
that travels along
neurons in the form of electrical energy
• Can be very slow or extremely fast
 Dendrites: branches
that receive
information
 Axon: carries the electrical impulse
 Axon terminal: branches that pass
information to other cells
 Stimuli: anything
that causes a change in
an organism
• Stimuli can be internal or external
 Response: reaction
to the stimuli
 Reflex: an involuntary and almost
immediate response to a stimuli
 Sensory neurons: use receptors to
gather information from in and around
your body
 Messages
are sent to the CNS from sensory
neurons for processing
• Involuntary- controlled automatically by the brain
• Voluntary- intentional actions controlled by the
brain
 Motor
neurons: neurons that send impulses
from the CNS to other systems
 Nerve: multiple axons bundled with blood
vessels and connective tissue to transmit
information
Nervous System
CNS
Brain
Cerebrum
(thinking,
senses,
memories,
voluntary)
PNS
Spinal Cord
Medulla
(involuntary)
Cerebellum
(movement,
balance,
posture)
Sensory
(receive)
Motor
(send)
Somatic
(voluntary)
Autonomic
(involuntary)
Sympathetic
(fight/flight)
Parasympathetic
(rest & digest)
 Would
you like to have a neurological
condition where you were unable to feel
pain?

https://www.youtube.com/watch?v=Z0AQ7lRCem4