Ch. 14 Spinal Cord, PNS

To avoid damaging the spinal cord during a spinal tap, the needle should be inserted _____. A) below L1- L2 B) near the lumbar enlargement C) between T2- T8 D) above C1

A) below L1- L2

The spinal cord ends at the _____. A) conus medullaris B) dorsal ganglion C) cauda equina D) filum terminale

A) conus medullaris

A nerve plexus __________. A) is a tangled bundle of spinal nerves formed by the fusion of multiple ventral rami B) are tangles of spinal nerves that supply sensory information alone to various areas of the spinal cord C) is a tangle of axons found within the spinal cord that supply given areas of the body D) is a branching of spinal nerves found in the hands and feet to supply sensation to the fingers and toes

A) is a tangled bundle of spinal nerves formed by the fusion of multiple ventral rami

The cervical enlargement _____. A) supplies nerves to the upper extremity B) contains only gray matter C) is the only enlargement in the spinal cord D) occurs in the proximal cervical segments from C1- C4

A) supplies nerves to the upper extremity

Which of the following is correctly matched? A) sacral—1 pair of spinal nerves B) cervical—7 pairs of spinal nerves C) thoracic—8 pair of spinal nerves D) lumbar—5 pair of spinal nerves

D) lumbar—5 pair of spinal nerves

The ulnar nerve is found in the ________ plexus. A) lumbar B) brachial C) sacral D) cervical E) thoracic

B) brachial

The H-shaped mass in the center of the spinal cord is mostly A) axons. B) gray matter. C) black matter. D) white matter. E) None of the answers are correct.

B) gray matter.

The ventral root of a spinal nerve transmits ________ information ________ the spinal cord. A) visceral; toward B) motor; away from C) motor; toward D) sensory; away from E) sensory; toward

B) motor; away from

Why are there 30 vertebrae but 31 pairs of spinal nerves? A) Between the C7 and T1 vertebrae there are two nerve pairs that exit the spinal cord. B) There are only 30 pairs of nerves, not 31. C) In the cervical area, there are eight nerve pairs, with the first exiting above C1. D) All nerves are named for the vertebrae superior to them, and there is an extra nerve in the coccygeal area.

C) In the cervical area, there are eight nerve pairs, with the first exiting above C1.

Moving from the superior to inferior ends of the spinal cord, give the order of the spinal regions and their correct number of nerve pairs. A) cervical (8), lumbar (6), thoracic (12), coccygeal (1), sacral (5) B) cervical (7), thoracic (13), lumbar (5), coccygeal (1), sacral (5) C) cervical (8), thoracic (12), lumbar (5), sacral (5), coccygeal (1) D) cervical (7), thoracic (12), lumbar (5), sacral (5), coccygeal (2)

C) cervical (8), thoracic (12), lumbar (5), sacral (5), coccygeal (1)

The spinal nerves enter and exit the vertebral canal through the A) transverse foramen. B) dorsal root. C) intervertebral foramen. D) vertebral foramen. E) ventral root.

C) intervertebral foramen.

In the correct order, the steps involved in a neural reflex are: (1) information processing (2) activation of a sensory neuron (3) arrival of a stimulus and activation of a receptor (4) activation of a motor neuron (5) response of a peripheral effector A) 2, 4, 5, 3, 1 B) 5, 4, 3, 2, 1 C) 1, 4, 5, 3, 2 D) 3, 2, 1, 4, 5 E) 1, 2, 3, 4, 5

D) 3, 2, 1, 4, 5

The spinal meninges __________. A) isolate the spinal cord from surrounding tissue B) protect the cord from injury that would be caused by rubbing against a vertebral foramen C) absorb shock transmitted up the body when walking, running, or other vigorous motions occur D) All of these responses are correct.

D) All of these responses are correct.

Which of the meninges is punctured when a woman in labor receives an epidural injection of anesthesia? A) The dura mater and arachnoid layer are punctured during an epidural injection, and the anesthesia is put into the subarachnoid space. B) The dura mater is punctured during an epidural injection. C) All of the meninges are punctured so the spinal cord can be numbed. D) None of the meninges is punctured, because the injection is in the epidural space.

D) None of the meninges is punctured, because the injection is in the epidural space.

The subarachnoid space is A) filled with fat. B) a potential space only. C) between the arachnoid mater and the periosteum. D) filled with cerebrospinal fluid. E) between the arachnoid mater and the underlying dura mater.

D) filled with cerebrospinal fluid.

The cervical plexus A) gives rise to the phrenic nerve, which provides the sole motor supply to the diaphragm. B) gives rise to motor branches that innervate the muscles of the neck. C) gives rise to branches that supply the skin of the neck, shoulder, and upper chest region. D) consists of the ventral rami of spinal nerves C1−C4, and some fibers from C5. E) All of the answers are correct.

E) All of the answers are correct.

The ventral root of a spinal nerve contains A) interneurons. B) axons of sensory neurons. C) ventral rami. D) cell bodies of motor neurons. E) axons of motor neurons.

E) axons of motor neurons.