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Flashcards in Nervous Tissue Deck (28):
1

peripheral nerve
-where are its axons located?

axons with cell bodies that are located
-within dorsal root ganglia at each spinal nerve segment
axons of motor neuron cell bodies located within ventral horn of spinal cord

2

sensory nerves
-other name
-function

afferent nerves
carry signals from receptors located throughout the body in the skin, muscles, connective tissue and visceral organs

3

motor nerves
-other name
-function

efferent
innervate all muscle tissue, voluntary striated, cardiac striated, and smooth muscle

4

each peripheral nerve we identify contains...
-called a...

contains both sensory and motor axons
called a mixed nerve

5

where is the only place the sensory and motor axons of the peripheral nerves are separated?

central to (before) the formation of the spinal nerve
-the dorsal and ventral roots

6

dorsal root
-contains
ventral root
-contains

dorsal: only sensory axons
ventral: only motor axons

7

the formation of the spinal nerve occurs near or within which structure

intervertebral foramen

8

distal to the formation of the spinal nerve, all identified nerve bundles are considered...

mixed nerves

9

all peripheral nerves are encased in...

a series of CT coverings

10

all nerve (CT) coverings consists of... (4)

mesoneurium
epineurium
perineurium
endoneurium

11

each of these layers is made up of CT with... (2)

its own innervation (nervi nervosum)
its own vascular supply (vasa nervosum)

12

mesoneurium
-alternate name
-function

name
-paraneurium (not to be confused with PERIneurium)
function
-covering of entire nerve that allows the nerve to move independently without being impinged or constricted by surrounding structures

13

constriction of a nerve can result in...

irritation of the nerve
-causes it to fire abnormally
-OR
-restrict the axons from propogating their respective action potentials

14

mesoneurium
-CT type

loose irregular CT

15

epineurium
-encapsulates...

encapsulates entire nerve
more intimately attached to CT compartments of the nerve itself
can be seen encasing larger groups of axons called fascicles

16

perineurium
-function

further subdivides nerve to smaller fascicles that begin to correspond closely to divisions heading toward specific muscles or dermatomes

17

endoneurium
-most closely associated with...

individual axons

18

functions of CT compartments of the axons of a peripheral nerve

allow for exchange of ions for actions potentials
allow for the exchange of nutrients and metabolites for the region of the nerve

19

what aspects of the peripheral nerve give it the ability to "stretch" to accommodate movement around joints or areas of possible restriction

elastic property of the CT
slightly undulating arrangement of individual axons

20

result of temporary compression of a peripheral nerve
-common names for this phemonemon

depletion of the vascular supply to the individual axons
-results in a loss of the ability to propagate action potentials
names
-foot or hand "falling asleep"

21

result of prolonged compression of a peripheral nerve

longer lasting effect on the nerve similar to that of temporary compression

22

what is the theory of adverse neural tension

includes the idea the the peripheral nervous system (PNS) is continuous with the central nervous system (CNS)
-with respect to both neural elements and CT elements

23

meninges
-composition

CT

24

outermost layer of the CNS
-name
-continuous with what part of the PNS?

dura mater
continuous within the intervertebral foramen with the epineurium

25

perineurium
-continuous with what parts of CNS

continuous in part with dura mater
continuous in part with pia mater (innermost meningeal covering)

26

endoneurium
-continuous with what part of the CNS

continuous with the pia mater

27

implications of the theory of adverse neural tension

stresses put on peripheral nerves in terms of stretch necessarily are transmitted to the CNS covering (meninges)

28

dura mater is connected with...
-what do these connections imply?

vertebrae
skull
implication
-movements of the spine may produce a stretch on the peripheral nervous system