Spinal Nerves Overview Flashcards
1
Q
nerve
A
- part of PNS
- hundreds of thousands of axons (each from a different neuron) wrapped in connective tissue
2
Q
ganglia
A
- collection of cell bodies of neurons (whose axons make up the nerve)
3
Q
cervical nerve pairs
A
8
4
Q
thoracic nerve pairs
A
12
5
Q
lumbar nerve pairs
A
5
6
Q
sacral nerve pairs
A
5
7
Q
coccygeal nerve pairs
A
1
8
Q
spinal nerves overview
A
- 31 pairs
- all mixed nerves
- branch out from spinal cord to innervate whole body
- each spinal nerve divides into branches (rami) almost immediately after leaving the vertebral column
9
Q
dorsal ramus
A
- smaller of the two ramii
- contains nerves serving dorsal trunk
- carries visceral + somatic motor, and sensory info to + from skin/muscles of back
10
Q
ventral ramus
A
- contains nerves serving ventral trunk, all limbs
- carries carries visceral + somatic motor, and sensory info to + from body surface, body wall structures, and limbs
11
Q
information transfer process
A
sensory information goes from:
stimuli > sensory receptors > spinal nerves > dorsal roots > spinal cord > brain
brain makes decision to move (sends motor command):
brain > spinal cord > ventral root > spinal nerve > muscle fiber > causes voluntary muscle contraction
12
Q
plexus
A
- network of interconnecting nerves
- formed when ventral ramii merge w/adjacent ventral ramii
- contains nerves w/fibers from various spinal nerves that have the same target organ
