anatomy and physiology: chapter 12

The outward projections from the central gray matter of the spinal cord are called - fibers. - horns. - pyramids. - wings. - tracts.

horns

The ________ plexus supplies innervation to the diaphragm. - lumbar - spinal - sacral - cervical - thoracic

- cervical

In the spinal cord, white matter is separated into ascending and descending tracts organized as - columns. - horns. - ganglia. - nuclei. - nerves.

- columns.

Spinal nerves - contain both sensory and motor. - contain only sensory fibers. - contain only motor fibers. - contain interneurons. - only carry information unidirectionally.

- contain both sensory and motor.

Which of the following associations is incorrect? - 1 coccygeal spinal nerve - 5 lumbar spinal nerves - 5 sacral spinal nerves - 8 cervical spinal nerves - 11 thoracic spinal nerves

- 11 thoracic spinal nerves

The spinal cord consists of five regions and ________ segments. - 5 - 25 - 31 - 12 - The number varies widely among individuals.

- 31

Describe a dermatome. (Module 12.5B) - A dermatome is the sensory region that can trigger spinal reflexes. - A dermatome is the total area of skin that contains sensory neurons. - A dermatome is the region of skeletal muscle that can respond to spinal reflexes. - A dermatome is the bilateral sensory region monitored by a single pair of spinal nerves. - A dermatome is the unilateral sensory region monitored by a single sensory nerve.

- A dermatome is the bilateral sensory region monitored by a single pair of spinal nerves.

What is a reflex? (Module 12.1B) - A reflex is a rapid, automatic response triggered by specific stimuli. - A reflex is a slow, calculated action triggered by repeated exposure to specific stimuli. - A reflex is a slow, calculated action involving input from the brain triggered by specific stimuli. - A reflex is when sensory inputs are sent quickly to the brain for analysis before any response occurs. - A reflex is a slow, calculated action triggered by a single exposure to specific stimuli.

- A reflex is a rapid, automatic response triggered by specific stimuli.

What is the significance of the cauda equina? (Module 12.2E) - It contains the axons of motor neurons that extend into the periphery to control somatic and visceral effectors. - It is made up of extensions of the posterior and anterior roots of spinal segments L2 to S5. It forms as the vertebral column continues to elongate after growth of the spinal cord ceases at about age 4. - It contains the cell bodies of sensory neurons whose axons carry information to the spinal cord. - It is the shallow longitudinal groove on the posterior surface of the spinal cord. - It is slender strand of fibrous tissue that extends from the inferior tip of the conus medullaris to the second sacral vertebra. It provides longitudinal support to the spinal cord as a component of the coccygeal ligament.

- It is made up of extensions of the posterior and anterior roots of spinal segments L2 to S5. It forms as the vertebral column continues to elongate after growth of the spinal cord ceases at about age 4.

Where does the simplest processing occur? (Module 12.11C) - corpus callosum - PNS and the spinal cord - cerebrum - brainstem - cerebellum

- PNS and the spinal cord

What purpose does reflex testing serve? (Module 12.15B) - Reflex testing provides information about sensory receptors. - Reflex testing provides information about the nervous system's functional status. - Reflex testing provides information about muscle strength. - Reflex testing provides information about the memory of a subject. - Reflex testing provides information about resting muscle tone.

- Reflex testing provides information about the nervous system's functional status.

The anterior root of a spinal nerve contains - axons of sensory neurons. - cell bodies of motor neurons. - interneurons. - cell bodies of sensory neurons. - axons of motor neurons.

- axons of motor neurons.

Each peripheral nerve provides ________ innervation to peripheral structures. - only motor - only sensory - both motor and sensory - either motor or sensory - motor and/or sensory

- both motor and sensory

In which plexus does the ulnar nerve arise? - lumbar - brachial - cranial - cervical - sacral

- brachial

Which of the following describes the posterior root ganglion? - contains axons of motor neurons - contains axons of sensory neurons - contains cell bodies of sensory neurons - contains cell bodies of motor neurons - contains interneurons

- contains cell bodies of sensory neurons

Reflexes that activate muscles on the opposite side of the body as the stimulus are called - bilateral. - ipsilateral. - contralateral. - collateral. - antilateral.

- contralateral.

The tough, fibrous, outermost covering of the spinal cord is the - arachnoid mater. - pia mater. - periosteum. - epidural space. - dura mater.

- dura mater.

The layer of connective tissue that surrounds individual axons within a peripheral nerve is termed the - subneurium. - epineurium. - endoneurium. - metaneurium. - perineurium.

- endoneurium.

The ________ space separates the dura mater from the walls of the vertebral canal. - epiarachnoid - epidural - subarachnoid - subdural - subpial

- epidural

The outermost connective- tissue covering of nerves is the - endoneurium. - perineurium. - endomysium. - epimysium. - epineurium.

- epineurium.

The ________ is a strand of fibrous tissue that provides longitudinal support as a component of the coccygeal ligament. - dorsal root - cauda equina - conus medullaris - ventral root - filum terminale

- filum terminale

Axons crossing from one side of the spinal cord to the other within the gray matter are found in the - lateral gray horns. - anterior gray horns. - white commissures. - posterior gray horns. - gray commissures.

- gray commissures.

Reflexes that activate muscles on the same side of the body as the stimulus are called - ipsilateral. - bilateral. - collateral. - antilateral. - contralateral.

- ipsilateral.

Spinal nerves from the sacral region of the cord innervate the ________ muscles. - leg - shoulder - intercostal - abdominal - facial

- leg

If a person has a crush injury to the C3- C5 spinal segments, you would expect that he - could walk without difficulty. - might be unable to breathe on his own. - would be in a coma. - would have full range of motion in all extremities. - would exhibit none of the above.

- might be unable to breathe on his own.

Reflexes, controlled by the spinal cord, act by - sensory input over cranial nerves to the spinal cord. - sensory input to reflex centers in the brain. - motor input to reflex centers in the spinal cord. - motor output over spinal nerves to effectors. - sensory output over cranial nerves to effectors.

- motor output over spinal nerves to effectors.

The white matter of the spinal cord is mainly - Schwann cells. - myelinated axons. - nodes of Ranvier. - unmyelinated axons. - neuroglia.

- myelinated axons.

A complex, interwoven network of nerves is called a - ramus. - spinal cord. - nerve plexus. - spinal plexus. - nerve ganglion.

- nerve plexus.

The layer of connective tissue that surrounds a fascicle within a peripheral nerve is the - epineurium. - endoneurium. - perineurium. - epimysium. - endosteum.

- perineurium.

The ________ nerve, which arises in the cervical plexus, innervates the diaphragm. - radial - ansa cervicalis - phrenic - sciatic - lesser occipital

- phrenic

The nerve crucial for breathing that originates within the cervical plexus is called the ________ nerve. - great auricular - transverse cervical - supraclavicular - ansa cervicalis - phrenic

- phrenic

The layer of the meninges in direct contact with the spinal cord is the - dura mater. - arachnoid mater. - subarachnoid space. - choroid plexus. - pia mater.

- pia mater.

List the components of a reflex arc. (Module 12.12B) - sensory neuron, interneuron, motor neuron - receptor, sensory neuron, motor neuron, effector, and sometimes interneurons may be involved - receptor, motor neuron, effector, and sometimes interneurons may be involved - sensory neuron and motor neuron - receptor, interneuron, effector

- receptor, sensory neuron, motor neuron, effector, and sometimes interneurons may be involved

Each of the following nerves originates in the lumbar plexus except the ________ nerve. - genitofemoral - saphenous - femoral - obturator - sciatic

- sciatic

If the posterior root of a spinal nerve is severed, - the spinal cord would not be able to process information at that level. - the brain would not be able to communicate with that level of the spinal cord. - sensory input would be blocked. - output to skeletal muscles would be blocked. - output to visceral organs would be blocked.

- sensory input would be blocked.

In the condition ________, a virus infects posterior root ganglia, causing a painful rash whose distribution corresponds to that of the affected sensory nerves as seen in their dermatomes. - shingles - myasthenia gravis - rubella - polio - mumps

- shingles

The anterior horns of the spinal cord contain mainly - nerve tracts. - sympathetic nuclei. - sensory nuclei. - autonomic motor nuclei. - somatic motor nuclei.

- somatic motor nuclei.

The specialized membranes that surround the spinal cord are termed the - cranial mater. - epidural membranes. - cranial meninges. - spinal meninges. - spinal mater.

- spinal meninges.

Where is spinal CSF located? (Module 12.3A) - between pedicles of adjacent vertebrae - intervertebral foramina - subarachnoid space - epidural space - subdural space

- subarachnoid space

Cerebrospinal fluid flows within the - pia mater. - subarachnoid space. - filum terminale. - dura mater. - arachnoid mater.

- subarachnoid space.