A&P 1: Ch 28 Spinal Cord, Spinal Nerves, and Meninges
How many spinal nerves are there?
31
How many pairs of thoracic nerves are there?
12
What is the subarachnoid space?
Contains cerebrospinal fluid and serves as a protective cushion for the spinal cord and brain.
At various levels of the spinal cord, many of the tracts ______________ to the opposite side of the spinal cord or brainstem
Decussate
Connections from pia mater to dura mater that anchor the spinal cord
Denticulate ligaments
What are the branches of spinal nerves?
Dorsal (posterior) root and ventral (anterior) root
The central canal of the spinal cord is located within the a. White matter b. Epidural space c. Gray commissure d. Subarachnoid space
Gray commissure
Follows irregular contours of spinal cord surface
Pia mater
The ___________________ is a groove that extends the length of the spinal cord posteriorly
Posterior median sulcus
Thin, weblike middle membrane
Arachnoid mater
The _______________ connects the gray matter on the left and right sides of the spinal cord
Gray commissure
What does the ventral (anterior) root contain?
Motor neurons
Lateral horn of gray matter
On the side
True or False? The brachial plexus is formed from components of spinal nerves C5-T1
True
True or False? There are eight pairs of cervical spinal nerves
True
How many pairs of lumbar nerves are there?
5
How many pairs of sacral nerves are there?
5
How many pairs of cervical nerves are there?
8
What is the spinal cord?
A column of nerve fibers that extends down through the vertebral canal
What is the dura mater?
A tough membrane with an epidural space containing blood vessels, loose connective tissue, and adipose tissue between the membrane and the vertebrae
What is the arachnoid mater?
Adheres to the inside of the dura mater
What is the pia mater?
Adheres to the surface of the spinal cord of the spinal cord and brain
The _______________ in the gray commissure of the spinal cord contains cerebrospinal fluid and is continuous with the cavities of the brain
Central canal
The bulge in the spinal cord that gives off nerves to the upper limbs is called the ______________ enlargement
Cervical
Outermost layer of meninges
Dura mater
The _____________ is the most superficial membrane of the meninges a. Subarachnoid space b. Pia mater c. Arachnoid mater d. Dura mater
Dura mater
What are the three layers of the meninges? (Superficial to deep)
Dura mater, arachnoid mater, pia mater
Separates dura mater from bone of vertebra or skull
Epidural space
True or False? The major ascending (sensory) and descending (motor) tracts compose the gray matter of the spinal cord
False
Inferior continuation of pia mater to the coccyx
Filum terminale
In a spinal cord cross section, the posterior _______________ of the gray matter resemble the upper wings of a butterfly
Horns
The inferior end to the adult spinal cord ends a. Inferior to L1 b. Inferior to L5 c. In the sacrum d. In the coccyx
Inferior to L1
What is a mixed nerve?
It is formed from a fusion of the dorsal and ventral roots. Both sensory and motor signals exist within the same nerve
Which of the following is not part of the gray matter of the spinal cord? a. Gray commissure b. Posterior horn c. Lateral funiculus d. Lateral horn
Lateral funiculus
The bulge in the spinal cord that gives off nerves to the lower limbs is called the _______________ enlargement
Lumbar
The dorsal root of spinal nerves contains a. Interneurons b. Sensory neurons c. Motor neurons d. Sensory and motor neurons
Sensory neurons
What does the dorsal (posterior) root contain?
Sensory neurons and dorsal root ganglion
The spinal cord gives rise to 31 pairs of _____________
Spinal nerves
Contains cerebrospinal fluid
Subarachnoid space
What makes up the Central Nervous System?
The brain and spinal cord
Gray Matter
The processing center for spinal reflexes and synaptic reflexes and synaptic integration
Intervertebral foramina
The site from where spinal nerves emerge from
The motor neurons are found in the _______________ roots of spinal nerves
Ventral
Cervical spinal nerve pair C1 originates between the occipital bone and the _______________
atlas
The white matter of the spinal cord is divided into anterior, lateral, and posterior ________________
funiculi
The gray matter of the spinal cord is divided into anterior, lateral, and posterior ________________
horns
Spinal nerves L4 through S4 form a _____________ plexus
sacral
