Lec 15 Nervous System 3 Peripheral Nervous System

Question 1

which pressure receptor responds to light pressure?

Answer 1

meissners corpuscles

Question 2

which pressure receptor responds to deep pressure?

Answer 2

pacinian corpuscles

Question 3

what is the purpose of proprioceptors?

Answer 3

3D acuity, position sense.

Question 4

what is the spinal nerve formed by?

Answer 4

both ventral and dorsal roots

Question 5

in order to have complete loss of sensation, how many dermatomes do you need to lose?

Answer 5

3 adjacent dermatomes

Question 6

which dermatome is located at the nipple?

Answer 6

T4

Question 7

which dermatome is located at the umbilicus?

Answer 7

T10

Question 8

what is referred pain?

Answer 8

sensory info coming from organs is perceived as rising from other locations

Question 9

what do branches of the dorsal primary rami supply?

Answer 9

muscles and skin of posterior head, neck, and back

Question 10

where is the cervical plexus located?

Answer 10

c1 - c4

Question 11

which nerve keeps you alive? where is it located?

Answer 11

phrenic nerve

c3, c4, c5

Question 12

where is the phrenic nerve sensory? where is it motor?

Answer 12

sensory : skin of neck

motor : diaphragm

Question 13

where is the brachial plexus located?

Answer 13

c5 - T1

Question 14

where is the brachial plexus sensory & motor?

Answer 14

sensory: skin of shoulder and upper limb

motor : muscles of shoulder and upper limb

Question 15

what are the branches of the brachial plexus? (upper body)

Answer 15

axillary, musculocutaneous, radial, ulnar, median

Question 16

what structures do the axillary nerve innervate?

Answer 16

sensory: skin of shoulder

motor : deltoid muscle

Question 17

what does a deficit of the axillary nerve cause?

Answer 17

cannot abduct

Question 18

what structures does the musculocutaneous nerve innervate?

Answer 18

sensory - skin of forearm

motor - biceps brachii, brachialis (muscles of anterior arm)

Question 19

what does a deficit of the musculocutaneous nerve cause?

Answer 19

cannot supinate / weak supination

no flexion of elbow

Question 20

what structures does the radial nerve innervate?

Answer 20

sensory : portions of posterior arm and forearm

motor : triceps, extensors of forearm

Question 21

what does a deficit of the radial nerve cause?

Answer 21

wrist drop (cannot extend wrist)

Question 22

what structures does the ulnar nerve innervate?

Answer 22

motor:
flexor carpi ulnaris
flexor digitorum (medial only)
lumbricals (medial only)

Question 23

what does a deficit in the ulnar nerve cause?

Answer 23

claw hand

Question 24

what structures does the median nerve innervate?

Answer 24

motor:
flexors of forearm
thenar eminence (thumb)
lumbricals (lateral 2)

Question 25

what does a deficit in the median nerve cause?

Answer 25

ape hand (loss of opposition of thumb)
carpal tunnel syndrome

Question 26

what does the femoral nerve innervate?

Answer 26

quadriceps

Question 27

what does a deficit in the femoral nerve cause?

Answer 27

no knee extension [no afferent signal if nerve is severed]

Question 28

where is the lumbosacral plexus located

Answer 28

L1 - S4

Question 29

what does the obturator innervate?

Answer 29

adductors, muscles of medial thigh

Question 30

what does a deficit in obturator cause?

Answer 30

no adduction in lower limb

Question 31

what are 2 branches of the sciatic nerve?

Answer 31

tibial, common fibular

Question 32

what are 2 branches of the common fibular nerve? what do each innervate?

Answer 32

deep fibular nerve: muscles of anterior leg

superficial fibular nerve: muscles of lateral leg

Question 33

what structures do the sciatic nerve innervate?

Answer 33

hamstrings

Question 34

what does a deficit in the sciatic nerve cause?

Answer 34

cant flex knees

Question 35

what structures does the tibial nerve innervate?

Answer 35

gastrocnemius, soleus, tibialis posterior (muscles of posterior leg)

Question 36

what does a deficit in the tibial nerve cause?

Answer 36

plantar flexion deficit

Question 37

what is pudendal nerve block used for?

Answer 37

childbirth

Question 38

what does loss of the pudendal nerve cause?

Answer 38

incontinence - loss of bladder control