Chapter 12: Peripheral Nervous System

Chapter 12: Peripheral Nervous System

Complete Chapter Questions With Answers

Sample Questions Are Posted Below

1. What is the most functionally important branch of the cervical plexus?
2. Branch to the sternocleidomastoid muscle
3. Branch to the biceps brachii
4. Branch to the triceps
5. Phrenic nerve
6. Musculocutaneous nerve

ANS: D

Rationale: The phrenic nerve is the most importand branch of the cervical plexus because it innervates the diaphragm.

2. Which one of the plexes innervates the posterior thigh and most of the leg and foot?
3. Cervical
4. Brachial
5. Lumbar
6. Sacral
7. None of the above

ANS: D

Rationale: The sacral plexus innervates the posterior thigh and most of the leg and foot.

3. Miniature endplate potentials are essential for which of the following?
4. Inhibiting the action of lower motor neurons
5. Initiating contraction of muscles
6. Preventing atrophy of muscle fibers
7. A and B
8. All of the above

ANS: C

Rationale: Miniature endplate potentials provide trophic factors to skeletal muscle fibers that are essential to prevent atrophy.

4. Trophic changes after denervation include which of the following?
5. Muscle atrophy
6. Shiny skin
7. Brittleness of fingernails and toenails
8. A and B
9. All of the above

ANS: E

Rationale: Tropic changes after denervation include muscle atrophy, shiny skin, and brittleness of fingernails and toenails.