Chapter 13: The Spinal Cord

Which are functions of the spinal cord?

-Conduction -Locomotion -Reflexes

Which spinal cord areas are composed of gray matter?

-Posterior Horn - Gray Commissure -Anterior horn

Place the spinal cord regions in order from superior to inferior.

1. Cervical 2. Thoracic 3. Lumbar 4. Sacral

The number of neurons in a descending pathway is _____ .

2

Each spinal cord segment gives rise to a pair of spinal nerves. How many pairs of spinal nerves are typically present in an adult?

31

What is the gray commissure of the spinal cord?

A band of gray matter connecting the gray matter of the left side with the gray matter of the right side

What is the cauda equina?

A bundle of nerve roots occupying the vertebral canal from L2 to S5

What is a region of the spinal cord supplied by a pair of spinal nerves called?

A segment

What is a fasciculus in the spinal cord?

A tract of nerve fibers within a funiculus

Which horns of the spinal cord contain the cell bodies of outgoing somatic motor neurons?

Anterior

The spinoreticular tract is found in which columns of the spinal cord?

Anterior and lateral

The spinothalamic tract is found in which columns of the spinal cord?

Anterior and lateral

Which meninx is just below (deep to) the dura mater?

Arachnoid mater

Within the spinal cord, which tracts carry information up to the brain?

Ascending

Where is the epidural space around the spinal cord?

Between the vertebral bones and the dural sheath

What is the white matter of the spinal cord?

Bundles of myelinated and unmyelinated axons found superficial to the gray matte

The bundle of nerves inferior to the medullary cone of the spinal cord is called the _____ _____ .

Cauda equina

In the spinal cord, what is the space within the gray commissure that contains CSF?

Central canal

Where do signals ascending through the spinocerebellar tract terminate?

Cerebellum

What does the central canal of the spinal cord contain?

Cerebrospinal fluid

Which ligament is formed by the fusion of the lumbar cistern and dura mater?

Coccygeal

The spinal cord contains ascending and descending nerve fibers that send information between the CNS and the periphery. This illustrates which function of the spinal cord?

Conduction

Functions of the spinal cord include which of the following?

Conduction, locomotion, reflexes

Which tract will have its origin and destination of opposite sides of the body?

Contralateral

In the spinoreticular tract, the second order neurons decussate to where?

Contralateral anterolateral system

Which are extensions of the pia mater that anchor the spinal cord?

Denticulate ligaments

Within the spinal cord, which tracts carry motor signals down from the brain?

Descending

The dural sheath around the spinal cord is formed from the _____ mater.

Dura

What is the dural sheath around the spinal cord made of?

Dura mater

What is the order of the meninges from superficial to deep?

Dura mater, arachnoid mater, pia mater

Pain during childbirth is often managed by injecting an anesthetic into which space?

Epidural

Which order neuron of the spinothalamic tract ends in the posterior horn at the point of entry to the spinal cord?

First

Which order neurons of the spinocerebellar tract originate at muscles and tendons?

First

How are the spinal cord regions named?

For the level of vertebral column from which its spinal nerves emerge

What structure marks the superior end of the spinal cord?

Foramen magnum

Where is the origin of sensory signals carried by the cuneate fasciculus?

From vertebra T6 and up

Nerve signals carried from the midthoracic and lower parts of the body are carried by which ascending tract?

Gracile fasciculus

What is the site of synaptic integration in the spinal cord?

Gray matter

Where does the first-order neuron of the spinothalamic tracts end?

In the posterior horn at the point of entry

Which tract will have its origin and destination on the same side of the body?

Ipsilateral

In an adult, the spinal cord ends at which vertebra?

L1

In descending tracts, which motor neuron innervates the target organ?

Lower

What is the name of the hollow space that contains the cauda equina and cerebrospinal fluid?

Lumbar cistern

What do muscle spindles monitor?

Muscle length and body movements

The spinoreticular tract carries what type of signals?

Pain

The denticulate ligaments are extensions of which meninx? Multiple choice question. Pia mater

Pia mater

Which meninx forms the terminal filum?

Pia mater

Which meninx is closely associated with the contours of the spinal cord?

Pia mater

The denticulate ligaments are extensions of which meninx?

Pia matter

What type of signal does the spinocerebellar tract carry?

Proprioception

Where do the second-order neurons of the spinoreticular tract terminate?

Reticular formation

In a sensory pathway, which neurons run from the spinal cord or brainstem to the thalamus?

Second-order

Which pathways are made up of three neurons?

Sensory

The anterior horns of the spinal cord contain the somas of which neurons?

Somatic motor

Signals for proprioception are carried by the anterior and posterior _____ tract.

Spinocerebellar

The cerebrospinal fluid circulates in the _____ space between the meninges.

Subarachnoid

In which does cerebrospinal fluid circulate?

Subarachnoid space

In the spinal cord, where is the white matter in relation to the gray matter?

Superficial

Where is the white matter in the spinal cord?

Superficial to the gray matter

The lateral horns of the spinal cord contain somas of which neurons?

Sympathetic motor

The lateral gray horns of the spinal cord are found in which segments of the spinal cord?

T2 to L1

The coccygeal ligament is formed from the fusion of which two structures?

Terminal filum and dura mater

Where do the third-order neurons of the spinoreticular tract run from the pons to?

Thalamus

What does contralateral mean?

That two points are on opposite sides of the body.

What does ipsilateral mean?

That two points are on the same side of the body

What is the cervical enlargement of the spinal cord?

The area of the spinal cord that gives rise to the nerves of the upper limbs

What is the subarachnoid space?

The space between the arachnoid mater and pia mater

In a sensory pathway, which neurons run from the thalamus to the sensory cerebral cortex?

Third-order

What are the regions of the spinal cord?

Thoracic, lumbar, cervical, sacral

How many neurons are typically found in an ascending pathway between the receptor and the brain?

Three

What is a bundle of nerve fibers within the white matter of the spinal cord called?

Tract

In descending pathways, which motor neurons have their somas in the cerebral cortex or brainstem?

Upper

What is the source of the sensory signals carried by the cuneate fasciculus?

Upper limbs and chest

The _____ horns of the spinal cord contain the cell bodies of outgoing somatic motor neurons.

anterior

The ______ median fissure is a longitudinal groove on the ventral surface of the spinal cord.

anterior

The spinoreticular tract is part of the _____ system in the anterior and lateral columns.

anterolateral

The spinothalamic tract is part of the ______ system in the anterior and lateral columns.

anterolateral

The mater is just below (deep to) the dura mater.

arachnoid

The lumbar cistern is the name of the hollow space that contains the _____ equina and cerebrospinal fluid.

cauda

The superior most region of the spinal cord is the ______ region.

cervical

The left and right sides of the gray matter in the spinal cord are connected by the gray _____ .

commisure

Because the nerve tracts of the spinal cord undergo _____ , the right side of the brain communicates with the left side of the body, and vice versa.

decussation

What factor accounts for the fact that the right side of the brain communicates with the left side of the body, and vice versa?

decussation

The _____ space is located between the vertebrae and the dural sheath around the spinal cord.

epidural

A ______ is a tract of nerve fibers within a column of the spinal cord.

fasciculus

The nerve fibers of the gracile fasciculus terminate at the _____ nucleus of the medulla oblongata.

gracile

The _____ matter of the spinal cord contains the synapses and therefore is the site of synaptic integration.

gray

Where are the neuron cell bodies, dendrites, and synapses found in the CNS?

gray matter

Fibers from the cuneate fasciculus end on the ______ side of the medulla oblongata.

ipsilateral

The subarachnoid space inferior to the medullary cone is called the ______.

lumbar cistern

The ______ enlargement is the area of spinal cord that gives rise to the nerves of the lower limbs and pelvis.

lumbosacral

The ______ are a series of fibrous connective tissue membranes covering the central nervous system.

meninges

The anterior horns of the spinal cord contain somas of somatic ______ neurons.

motor

The _____ mater is the meningeal layer that is closely associated with the contours of the spinal cord.

pia

The third-order neurons of the spinoreticular tract runs from the ______ to the thalamus.

pons

The _____ median sulcus is a longitudinal groove on the dorsal surface of the spinal cord.

posterior

The cuneate fasciculus is located in the ______ column of the spinal cord.

posterior

The space between the arachnoid mater and pia mater is called the _____ space.

subarachnoid

In the CNS, bundles of axons that make up white matter are called ______.

tracts

_____ matter is composed of myelinated and unmyelinated axons and is superficial to the gray matter of the spinal cord.

white