The master communication center of
the body.
3 Main Functions:
Monitor all information about
changes occurring both
inside and outside the body.
Process and interprets the
information received and
integrates it in order to make
decisions.
Our nervous system
Command responses by
allows us to feel pain.
activating muscles, glands,
and other parts of the
nervous system.
CNS
Brain &
Spinal Cord
PNS
Cranial Nerves
& Spinal Nerves
12 pairs of cranial nerves
32 pairs of spinal nerves
Functional Organization
Figure 7.2
Autonomic sensory
Autonomic motor
Neuron Anatomy
 Extensions outside
the cell body
 Dendrites –
conduct impulses
toward the cell
body
 Axons – conduct
impulses away
from the cell body
Figure 7.4a
Mad, Mad, Mad scientist
Axon terminals
Cell body
Nucleus
Dendrites
Axon
Myelin sheath
Physiology of Neurons
 Sensory (afferent) neurons
 Carry impulses from the sensory
receptors
 Cutaneous sense organs
 Proprioceptors – detect stretch or
tension
 Motor (efferent) neurons
 Carry impulses from the central
nervous system
Neuron Classification
Figure 7.6
Sensory neuron
(Afferent)carry
impulses from
receptors to
CNS
relay neuron
impulses from
sensory to
motor nerves
Motor neuron
(Efferent) carry
impulses from CNS
to effector (muscle
or gland)
Axons and Nerve Impulses
 Axons end in axonal terminals
 Axonal terminals contain vesicles with
neurotransmitters
 Axonal terminals are separated from the
next neuron by a gap
 Synaptic cleft – gap between adjacent
neurons
 Synapse – junction between nerves
Nerve Fiber Coverings
 Schwann cells –
produce myelin
sheaths
 Nodes of Ranvier –
gaps in myelin
sheath along the
axon
Figure 7.5
Structural Classification of Neurons
 Multipolar neurons – many extensions
from the cell body
Figure 7.8a
Structural Classification of Neurons
 Bipolar neurons – one axon and one
dendrite
Figure 7.8b
Structural Classification of Neurons
Unipolar neurons – have a short
single process leaving the cell body
Figure 7.8c
Each table with find information regarding a
different type of “supporting” neuron to
share with the class.
Each table has been assigned a cell type.
Use your book to fill in the requested information about the
various Glial cells: Astrocyte, Microglia, Ependymal,
Oligodendrocyte, and Schwann cells.
Select a representative to speak for your table – he are she
must come up to the front of the class.
You have 7 minutes to gather the information.