Chapter 13: The spinal cord, spinal nerves, and reflex

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

Anterior and lateral

Which nerve tract is indicated in the figure?

Anterolateral system

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

Ascending

Where does the spinal cord arise from the medulla oblongata?

At the foramen magnum

What is the white matter of the spinal cord?

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

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 nerve tract is indicated in the figure by the letter A?

Cuneate fasciculus

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

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

Dura mater, arachnoid mater, pia mater

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

First

In a sensory pathway, which neuron detects the stimulus and transmits the signal to the spinal cord or brainstem?

First order

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

Where do the nerve fibers of the gracile fasciculus terminate in the medulla oblongata?

Gracile nucleus

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

L1

Within the spinal cord, what type of information do the descending tracts carry?

Motor

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

The area indicated in the figure contains two tracts.What are they?

Spinothalamic tract Spinoreticular tract

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 source of the sensory signals carried by the cuneate fasciculus?

Upper limbs and chest

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

anterolateral

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

In a sensory pathway, the ______ order neuron detects the stimulus and transmits the signal to the spinal cord or brainstem.

first

The tract indicated in the figure by the letter A is the ______ fasciculus.

gracile

Which nerve tracts do not decussate?

ipsilateral

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

meninges

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

posterior

Which pathways are made up of three neurons?

sensory

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

three

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

white