A peripheral collection of nerve cell
bodies together with afferent and
efferent axons
Dorsal root ganglia are sensory
cells within the spinal nerves
Efferent motor ganglia in ANS
Cranial nerve ganglia
Nerves - bundles
of axons
Spinal nerves
connected to spinal cord
and cranial nerves
connected to brain
Epineurium surrounds entire nerve trunk
Perineurium surrounds axons and
endoneurium to form fassicles
Endoneurium surrounds individual axons
Motor - from CNS
Sensory - to CNS
Mixed- sensory and motor
CNS
Spinal Cord
Begins at base of medulla oblongata +
extends as slender cord to level of
intervertebral disc between the first
and second lumbar vertebrae
31 segements each with a pair of
spinal nerves
Spinal nerves
8 Cervical
12 Thoratic
5 Lumbar
5 Sacral
1 coccygeal
Link information to and
from brain
Spinal reflexes
Sagital section of lower spine
Inferior terminal at level of the 2nd
lumbar vertabra. Branches from
lumbar region pass downward from
cone-shaped tip (conus medullaris)
of spinal cord forming cauda
equina (horse's tail)