Peripheral Nervous System

Question 1

the CNS consists of the

Answer 1

brain and spinal cord

Question 2

the PNS consists of

Answer 2

cranial nerves, spinal nerves, and ganglia

Question 3

a ganglion is a

Answer 3

collection of neuron cell bodies outside the CNS

Question 4

sensory innervation brings information

Answer 4

to the CNS from the environment

Question 5

motor innervation sends instructions

Answer 5

from the CNS to muscle and glands

Question 6

glands

Answer 6

specialized sections of epithelia which secrete something

Question 7

bell bodies of motor neurons are found within the

Answer 7

CNS

Question 8

cell bodies of sensory neurons are found

Answer 8

outside of the brain and spinal cord in ganglia

Question 9

sensory neuron cell body is in the middle of

Answer 9

2 axons

Question 10

somatic innervation concerns the

Answer 10

body wall

Question 11

example of somatic innervation

Answer 11

innervation of skeletal muscle and skin

Question 12

visceral innervation concerns the

Answer 12

internal organs

Question 13

example of visceral innervation

Answer 13

innervation of the heart

Question 14

the functional dichotomies of the nervous system intersect as

Answer 14

body wall:
somatic sensory
somatic motor

internal organs:
visceral sensory
visceral motor

Question 15

somatic motor innervation target tissue

Answer 15

skeletal muscle

Question 16

somatic motor innervation control is usually

Answer 16

conscious (voluntary)

Question 17

in somatic motor innervation, one neuron connects the CNS to

Answer 17

the target muscle

Question 18

neurons have to be long because

Answer 18

the spinal cord has to connect to the limbs

3-4 ft

Question 19

somatic sensory innervation carries sensory information about the

Answer 19

external environment

Question 20

somatic sensory innervation carries information from the (2)

Answer 20

skin and musculoskeletal system

Question 21

somatic sensory innervation is usually perceived

Answer 21

consciously

ex. temp of the room, pressure of the seat

Question 22

in somatic sensory innervation, how many neurons connect the site of stimulus to the CNS?

Answer 22

1

Question 23

examples of somatic sensory stimuli (5)

Answer 23

pain from cutting, tearing, crushing, inflammation, or burning (heat or chemical)
temperature
touch
pressure
vibration

Question 24

for somatic sensory stimuli, think of stimuli that can be

Answer 24

felt by the skin

Question 25

notochord marks the

Answer 25

midline of the embryo

Question 26

paraxial mesoderm gives rise to (3)

Answer 26

bone
skeletal muscle
dermis

Question 27

mesoderm

Answer 27

generalized tissue which will make the body wall

Question 28

the paraxial mesoderm is a

Answer 28

continuous column that runs on either side of the notochord

Question 29

– pairs of somites

Answer 29

37

Question 30

the 37 pairs of somites:

Answer 30

4 occipital 
8 cervical
12 thoracic
5 lumbar
5 sacral
3 coccygeal

Question 31

• pairs of somitomeres

Answer 31

7

Question 32

dermamyotome gives rise to

Answer 32

dermis and skeletal muscle

Question 33

sclerotome gives rise to

Answer 33

bone (hard)

Question 34

the epiaxial dermamyotome is closer to the

Answer 34

midline
smaller
close to the central axis of the body

Question 35

hypaxial dermamyotome is

Answer 35

below the axis

larger

Question 36

dermamytotome=

Answer 36

dermatome (dermis)

myotome (muscle)

Question 37

the epaxial dermamyotomes give rise to all of the

Answer 37

intrinsic (deep) back muscles as well as the dermis that covers them
*they give rise to nothing else

Question 38

the hypaxial dermamyotomes give rise to

Answer 38

all of the other skeletal muscle and dermis below the neck, including the limbs
*everything else

Question 39

innervation and blood supply must be available to each

Answer 39

individual somite

Question 40

epaxial and hypaxial dermamyotomes have separate

Answer 40

blood supplies

Question 41

the spinal cord is functionally

Answer 41

segmented

Question 42

each level of the spinal cord has

Answer 42

cell bodies that serve the tissues that originate from the same level, including a somite pair

Question 43

each somite pair is associated with a pair of

Answer 43

spinal nerves

Question 44

each spinal nerve is associated with a pair of

Answer 44

somites

Question 45

spinal nerves are numbered from

Answer 45

superior to inferior

Question 46

why is there 37 somites but only 31 spinal nerves?

Answer 46

somites at the extreme ends do not have spinal nerve innervation (occipital and tail end)

Question 47

S5 and Co1 spinal nerves are

Answer 47

dermatome only

Question 48

all spinal nerves have

Answer 48

somatic sensory components

Question 49

all spinal nerves have somatic motor components, except

Answer 49

S5 and Co1

Question 50

parasympathetics are only found in the spinal nerves

Answer 50

S2-S4

Question 51

there is a one-neuron pathway between the spinal cord and the target, which is

Answer 51

skeletal muscle

Question 52

cell bodies are in the

Answer 52

ventral horn of the spinal cord gray matter

Question 53

somatic motor axons leave the spinal cord via the

Answer 53

ventral roots of spinal nerves

Question 54

because the muscles supplied by a spinal cord segment supply muscle from different embryonic primordia, each spinal nerve has to branch into a

Answer 54

dorsal ramus and ventral ramus

Question 55

intrinsic (deep) back muscles are derived from

Answer 55

epaxial dermamyotomes

Question 56

intrinsic (deep) back muscles are supplied by

Answer 56

dorsal rami

Question 57

all other skeletal muscles below the head are derived from

Answer 57

hypaxial dermemyotomes

Question 58

all other skeletal muscles below the head are supplied by

Answer 58

ventral rami