Chap 14 - Part 2

Question 1

Arrange the following structures from spinal cord out:

Spinal nerve / anterior and posterior roots / anterior and posterior rami / anterior and posterior rootlets

Answer 1

Posterior and anterior rootlets

Posterior and anterior roots

Spinal nerve

Posterior and anterior rami

Question 2

What are differences between an anterior Ramus and a posterior Ramus of a spinal nerve

Answer 2

Posterior- smaller of the two, serves skin and muscles of the back

Anterior - larger of the two, travels to anterior side of body and upper and lower limbs

Question 3

What is a dermatome

Answer 3

Segment of skin supplied by single spinal nerve

Question 4

Why may a dermatome be clinically significant

Answer 4

Can indicate damage to one or more spinal nerves

Important in shingles

Question 5

Define nerve plexus

Answer 5

Rami of the cervical, lumbar, and sacral spinal nerves come together to form networks of nerves

Question 6

What is the benefit of nerve plexus, rather than a single nerve innervates a body structure

Answer 6

Innervation to muscle or skin is not totally lost due to nerve damage

Question 7

What are the 4 main nerve plexuses

Answer 7

Cervical

Brachial

Lumbar

Sacral

Question 8

The phrenic nerve is part of the ______ plexus and it innervates the ______.

Answer 8

Cervical

Diaphragm

Question 9

What are the five main nerves of the brachial plexus

Answer 9

Axillary nerve

Radial nerve

Median nerve

Musculocutaneous nerve

Ulnar nerve

Question 10

What are main nerve of lumbar plexus

Answer 10

Femoral nerve

Obturator nerve

Question 11

The _____ nerve of the _______ plexus innervates the anterior thigh muscles as well as the skin of the anterior and inferomedial thigh, medial side of leg, and most medial aspect of foot

Answer 11

Femoral nerve

Lumbar plexus

Question 12

Which nerve of lumbar plexus may be damaged if you have difficulty extending knee?

Answer 12

Femoral nerve

Question 13

The sciatic nerve of the _______ plexus is composed of the ______ and ________ ________ nerves

Answer 13

Sacral

Tibial nerve

Common fibular nerve

Question 14

Sciatic nerve innervates (the anterior / posterior) thigh and leg muscles, plantar foot muscles as well as short head of the biceps femoris muscle

Answer 14

Posterior

Question 15

What are the five steps in reflex arc

Answer 15

1Stimulus activates receptor
2Signal is sent through sensory neuron to spinal cord
3Nerve signal is processed by Interneurons
4Nerve signal sent through motor neuron to effector
5Effector responds

Question 16

What is reflex arc

Answer 16

Rapid involuntary responses of muscles or glands

Question 17

Structures involved in a reflex arc

Answer 17

Skin

Sensory neuron
Interneurons (spinal cord)
Motor neuron

Effector

Question 18

Difference between monosynaptic and polysynaptic reflexes

Answer 18

Mono- simplest of all reflexes, very minor delay

Poly- more complex reflex, more prolonged delay

Question 19

What are the four common spinal reflexes

Answer 19

Stretch reflex

Withdrawal reflex

Golgi tendon reflex

Crossed extensor reflex

Question 20

What is the difference between sensory (ascending) and motor (descending) pathways in terms of the direction of nerve signal

Answer 20

Sensory- signals from sensory receptors ascend to brain

Motor- signals from brain descend to muscles or glands