Question 1

A patient suffers a spinal cord injury at the level of L2. Which anatomical structure marks the typical end of the adult spinal cord, and what is the clinical significance of this location for procedures such as lumbar puncture?

Accepted Answer

The conus medullaris; it marks the end of the spinal cord, so lumbar punctures are performed below this level to avoid damaging the spinal cord.

Question 2

Which of the following best describes the function of the white matter in the spinal cord?

Accepted Answer

It consists of myelinated and unmyelinated axons that carry information up and down the spinal cord.

Question 3

During a withdrawal reflex, such as pulling your hand away from a hot object, which of the following neural circuit patterns is primarily responsible for coordinating the simultaneous activation of multiple muscle groups?

Accepted Answer

Divergence

Question 4

A patient presents with a loss of sensation and a painful rash along a single dermatome. Which virus is most likely responsible, and what is the anatomical explanation for the pattern of symptoms?

Accepted Answer

Varicella-zoster virus; it infects the posterior root ganglion, causing symptoms along the affected dermatome.

Question 5

Which meningeal layer is most closely associated with the blood vessels supplying the spinal cord, and in which space are these vessels primarily located?

Accepted Answer

Pia mater; subarachnoid space

Question 6

A patient with polio loses the use of his leg muscles. Which region of the spinal cord is most likely affected?

Accepted Answer

Anterior gray horn

Question 7

Which of the following best describes the path of sensory information from the skin of the back to the spinal cord?

Accepted Answer

Posterior ramus → posterior root → spinal cord

Question 8

Which nerve, if damaged, would most likely result in paralysis of the diaphragm and severe breathing difficulties?

Accepted Answer

Phrenic nerve

Question 9

Which of the following statements about the stretch reflex is correct?

Accepted Answer

It is a monosynaptic reflex that helps maintain muscle length and posture.

Question 10

A patient exhibits a positive Babinski reflex after a spinal cord injury. What does this indicate about the patient's nervous system?

Accepted Answer

There is damage to descending motor tracts, resulting in loss of inhibition of the reflex.

Question 11

Which of the following best explains why the cauda equina is a safe site for lumbar puncture?

Accepted Answer

It contains only nerve roots, not the spinal cord, reducing the risk of direct spinal cord injury.

Question 12

Which of the following neural circuit patterns allows for the same motor neuron to receive both conscious and unconscious control, such as in breathing?

Accepted Answer

Convergence

Question 13

Which of the following is NOT a function of the spinal meninges?

Accepted Answer

Producing cerebrospinal fluid

Question 14

Which of the following best describes the organization of white matter in the spinal cord?

Accepted Answer

It is organized into columns containing ascending and descending tracts.

Question 15

A patient is unable to extend his wrist and fingers after a humeral fracture. Which nerve of the brachial plexus is most likely damaged?

Accepted Answer

Radial nerve

Question 16

Which of the following best describes the difference between a monosynaptic and a polysynaptic reflex?

Accepted Answer

A monosynaptic reflex has a single synapse between sensory and motor neurons, while a polysynaptic reflex involves one or more interneurons.

Question 17

Which of the following is a property of polysynaptic reflexes, such as the withdrawal reflex?

Accepted Answer

They may involve reverberating circuits that prolong the response.

Question 18

Which of the following best describes the function of the rami communicantes in spinal nerves T1–L2?

Accepted Answer

They carry motor output of the sympathetic division of the autonomic nervous system.

Question 19

Which of the following best explains the clinical value of mapping sensory perception in the hand and foot?

Accepted Answer

It helps determine the location of damage to specific peripheral nerves.

Question 20

Which of the following best describes the effect of the Jendrassik maneuver on the patellar reflex?

Accepted Answer

It facilitates the reflex by increasing the excitability of motor neurons, resulting in a larger response.

Study Notes: The Spinal Cord, Spinal Nerves, and Spinal Reflexes

Study Guide - Practice Questions

Study Guide - Flashcards