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
