Ch 13.- The spinal cord, spinal nerves, and somatic reflexes

There are __________ pairs of spinal nerves. A. 12 B. 24 C. 31 D. 35 E. 62

C. 31

Which of the following is contained within gray matter? A. Glial cells, axons of motor neurons, and Schwann cells B. Glial cells and myelinated fibers C. Neurosomas, dendrites, and proximal parts of axons of neurons D. The distal part of axons of lower order motor neurons E. Glial cells only

C. Neurosomas, dendrites, and proximal parts of axons of neurons

Which of the following is not a distal branch of the spinal nerve? A. Anterior ramus B. Posterior ramus C. Posterior root D. Meningeal branch E. Communicating rami

C. Posterior root

Motor commands are carried by __________ from the brain along the spinal cord. A. both anterior and posterior roots B. ascending tracts C. spinal nerves D. cranial nerves E. descending tracts

E. descending tracts

The upper motor neurons that control skeletal muscles begin with a soma in the __________. A. posterior horn of the spinal cord B. anterior horn of the spinal cord C. motor association cortex of the cerebrum D. postcentral gyrus of the cerebrum E. precentral gyrus of the cerebrum

E. precentral gyrus of the cerebrum

Which of the following branches of a spinal nerve has the somas of only sensory neurons? A. Posterior (dorsal) root B. Anterior (ventral) root C. Posterior ramus D. Anterior ramus E. Meningeal branch

A. Posterior (dorsal) root

Voluntary motor impulses leave the spinal cord via the _________ of gray matter. A. anterior horn B. posterior horn C. anterior column D. posterior column E. lateral horn

A. anterior horn

Neurosomas of the anterior root are located in the __________. A. gray matter B. posterior root ganglion C. white matter D. anterior rootlets E. anterior root ganglion

A. gray matter

Second-order neurons synapse with third-order neurons in the __________. A. thalamus B. dorsal root ganglion C. spinal cord D. cerebral cortex E. medulla oblongata

A. thalamus

Which of the following structures is the richest in lipid content? A. Gray matter B. White matter C. Arachnoid mater D. Dura mater E. Pia mater

B. White matter

Many upper motor neurons synapse with lower motor neurons in the ___________. A. posterior horn B. anterior horn C. posterior column D. anterior column E. posterior root ganglion

B. anterior horn

The bundle of nerve roots that occupy the vertebral canal from L2 to S5 is called the __________. A. medullary cone B. cauda equina C. lumbar enlargement D. cervical enlargement E. spinal cord

B. cauda equina

A reflex in which the sensory input and motor output are on opposite sides of the spinal cord, is called a(n) _________ reflex arc. A. intersegmental B. contralateral C. ipsilateral D. polysynaptic E. monosynaptic

B. contralateral

The signals that control your handwriting travel down the spinal cord in the _________ tracts. A. tectospinal B. corticospinal C. lateral vestibulospinal D. medial vestibulospinal E. spinocerebellar

B. corticospinal

Epidural anesthesia is introduced to the epidural space between the __________ to block pain signals during pregnancy. A. dural sheath and dura mater B. dural sheath and vertebral bones C. dura mater and arachnoid mater D. arachnoid mater and pia mater E. dura mater and pia mater

B. dural sheath and vertebral bones

Which one of the following best describes the order of a somatic reflex? A. Somatic receptor-> interneuron->afferent nerve fiber-> efferent nerve fiber-> skeletal muscle B. Somatic receptor-> efferent nerve fiber-> interneuron-> afferent nerve fiber-> skeletal muscle C. Somatic receptor-> afferent nerve fiber-> interneuron-> efferent nerve fiber->skeletal muscle D. Somatic receptor-> efferent nerve fiber-> afferent nerve fiber-> interneuron-> skeletal muscle E. Somatic receptor-> afferent nerve fiber-> interneuron-> efferent nerve fiber-> smooth muscle

C. Somatic receptor-> afferent nerve fiber-> interneuron-> efferent nerve fiber->skeletal muscle

Which of the following sensory functions involves neurons in the posterior root ganglion? A. Smell B. Hearing C. Touch D. Taste E. Vision

C. Touch

A ganglion is a _________. A. bundle of axons in the CNS B. cluster of dendrites in either the CNS or the PNS C. cluster of neurosomas in the PNS D. bundle of axons in the PNS E. cluster of neurosomas in the CNS

C. cluster of neurosomas in the PNS

A nurse pricks your finger to type your blood. You flinch at the pain, pulling your hand back. This is called the __________ reflex. A. painful B. stretch C. flexor (withdrawal) D. tendon E. crossed extension

C. flexor (withdrawal)

A __________ is a cordlike organ composed of numerous __________. A. nerve fiber; nerves B. nerve fiber; axons C. nerve; axons D. nerve fiber; neurosomas E. nerve; neurosomas

C. nerve; axons

The structure found between the posterior rootlets and the posterior root ganglion is called the __________. A. anterior horn B. anterior root of a spinal nerve C. posterior root of a spinal nerve D. posterior horn E. spinal nerve

C. posterior root of a spinal nerve

Which of the following is not considered a region of the spinal cord? A. Cervical B. Thoracic C. Lumbar D. Pelvic E. Sacral

D. Pelvic

The middle layer of the meninges is called the __________. A. gray matter B. white matter C. dura mater D. arachnoid mater E. pia mater

D. arachnoid mater

Cerebrospinal fluid fills the space between the __________. A. dural sheath and dura mater B. dural sheath and vertebral bones C. dura mater and arachnoid mater D. arachnoid mater and pia mater E. dura mater and pia mater

D. arachnoid mater and pia mater

"Somatosensory" does not refer to sensory signals from __________. A. bones and muscles B. joints C. proprioceptors D. the viscera E. the skin

D. the viscera

Which of the following fractures would be the least likely to cause a spinal cord injury? A. A fracture of vertebra C2 B. A fracture of vertebra C6 C. A fracture of vertebra T5 D. A fracture of vertebra T12 E. A fracture of vertebra L4

E. A fracture of vertebra L4

Which of the following is an ascending tract of the spinal cord? A. Lateral tectospinal tract B. Medial reticulospinal tract C. Ventral corticospinal tract D. Vestibulospinal tract E. Gracile fasciculus

E. Gracile fasciculus