CHAPTER 12: Spinal Cord and Spinal Nerves

There are ________ cervical spinal nerves.

8

Identify the layers of meninges and the related spaces from most superficial to deepest. Epidural Space Subdural Space Subarachnoid Space Dura Mater Arachnoid Mater Pia Mater

Epidural Space Dura Mater Subdural Space Arachnoid Mater Subarachnoid Space Pia Mater

What type of reflex prevents contracting muscles from applying excessive tension on tendons by inhibiting muscle contraction?

Golgi tendon reflex

A patient is having difficulty breathing. Name a nerve could be responsible for this difficulty.

Phrenic nerve

Identify the three layers of meninges.

Pia mater Dura mater Arachnoid mater

Identify the function of Golgi tendon reflexes.

Protect muscles and tendons from damages caused by excessive tension

Which is a nerve of the lumbosacral plexus?

Pudendal nerve

The femoral nerve innervates which muscle group?

Quadriceps

Which two nerves converge to form the Sciatic nerve?

Tibial and common fibular nerves

The distal branches of spinal nerves divides into the Rami. Which ramus branches to form the major nerve plexuses?

Anterior (Ventral) ramus

Which spinal tracts are exclusively sensory?

Ascending tracts

Identify the nerve that innervates the deltoid and teres minor and the skin of the shoulder.

Axillary nerve

There is/are ________ pair(s) of cervical nerve(s), ________ pair(s) of thoracic nerve(s), ________ pair(s) of lumbar nerve(s), ________ pair(s) of sacral nerve(s) and 1 pair of coccygeal nerve.

Blank 1: 8 or eight Blank 2: 12 or twelve Blank 3: 5 or five Blank 4: 5 or five

When considering spinal nerves, there are 8 pairs of ________ nerves, 12 pairs of ________ nerves, 5 pairs of ________ nerves, 5 pairs of sacral nerves and 1 pair of ________ nerves.

Blank 1: cervical Blank 2: thoracic Blank 3: lumbar Blank 4: coccygeal

Name the plexus which supplies innervation to the muscles acting on the scapula and innervates the skin of the medial arm and forearm.

Brachial plexus

Tibial nerve

Branches to form the medial and lateral plantar nerves

The brain and the spinal cord make up the ____.

Central Nervous System (CNS)

Identify the nerves that combine to form the sciatic nerve.

Common fibular nerve Tibial nerve

The phrenic nerve innervates the ______.

diaphragm

The ________ rami of spinal nerves innervate most of the deep muscles of the back and muscles of the trunk responsible for moving the vertebral column.

dorsal

The sensory root of a spinal nerve is also referred to as __________ root.

dorsal

The thickest of the meninges is the __________.

dura mater

Two areas of the spinal cord are thicker than the rest. These areas give rise to the nerves leading to the limbs. These areas are called the cervical and lumbar ________.

enlargements

True or false: Spinal nerves are named for the region of the body that they innervate.

false

True or false: The spinal cord contains two enlargements. One of these enlargements is found in the cervical area and the other is in the thoracic region.

false

Which matter of the spinal cord contains neuron cell bodies?

gray

common fibular nerve

lateral and anterior lower leg

Ventral roots consist of only ________ fibers (axons).

motor or efferent

The cross-sectional view of the spinal cord reveals white matter on the

outside, gray matter on the inside, and a ventral motor root.

The diaphragm is innervated specifically by the ________ nerve(s).

phrenic

Damage to which of these nerves would be most life-threatening?

phrenic nerves

The deepest meningeal layer that is tightly attached to the spinal cord is called the ________ mater.

pia

Which is the deepest layer of the meninges?

pia mater

Major branches of a spinal nerve are called _____.

rami

Spinal nerves exiting the spinal cord from the level of L4 to S4 form the __________ plexus.

sacral

The tibial and common fibular nerve combine to form the ______ nerve.

sciatic

If the ventral root of a spinal nerve were cut, the regions innervated by that spinal nerve would experience complete loss of __________.

sensation

Dorsal (posterior) roots consist of only ______ fibers (axons).

sensory

The reflex where muscles contract in response to stretching within the muscle is called a ________ reflex.

stretch

The space between the arachnoid mater and pia mater is the ________ space.

subarachnoid

The space related to the meninges that contains cerebrospinal fluid is the _____.

subarachnoid space

The coccygeal plexus innervates _____.

the muscles of the pelvic floor

True or false: The gluteal nerve is a nerve of the lumbosacral plexus.

true

When a person hits their "funny bone," they cause temporary damage to the __________ nerve.

ulnar

A nerve plexus is formed when the ________ rami of different spinal nerves intermingle.

ventral

Motor axons are found in ______ roots.

ventral

The _____ rami of spinal nerves innervate the ribs, the intercostal muscles and the skin of the thorax.

ventral

The ______ rami form nerve plexuses.

ventral

The motor root of a spinal nerve is also referred to as the __________ root.

ventral

Match each nerve of the brachial plexus with the correct region that it innervates. 1. Axillary nerve 2. Radial nerve 3. Musculocutaneous nerve 4. Ulnar nerve 5. Median nerve

1. Axillary nerve - Inferior lateral shoulder 2. Radial nerve - Posterior surface of arm, forearm and lateral two-thirds of dorsum of hand 3. Musculocutaneous nerve - Anterior portion of arm 4. Ulnar nerve - Medial one-third of hand, little finger and middle half of ring finger 5. Median nerve - Lateral two-thirds of palm, anterior thumb, index, and middle fingers, dorsal tips of thumb, index, middle, and ring fingers

Correctly pair each nerve of the brachial plexus with the correct region that it innervates. 1. Axillary nerve 2. Radial nerve 3. Musculocutaneous nerve 4. Ulnar nerve 5. Median nerve

1. Axillary nerve - Part of the shoulder 2. Radial nerve - Posterior portion of arm, forearm and hand 3. Musculocutaneous nerve - Anterior portion of arm 4. Ulnar nerve - Anterior portion of forearm and hand 5. Median nerve - Similar to the ulnar nerve

Match the connective tissue component of a nerve with the correct description. 1. Endoneurium 2. Perineurium 3. Epineurium

1. Delicate layer of connective tissue surrounding a single axon and its Schwann cell sheath (Endoneurium) 2. Layer of connective tissue surrounding a nerve fascicle (Perineurium) 3. A layer of dense connective tissue surrounding a nerve(Epineurium)

Indicate the correct order of meninges from superficial at the top to deep at the bottom.

1. Dura mater 2. Arachnoid mater 3. Pia mater

List the layers of connective tissue surrounding nervous tissue starting with the most superficial layer and ending with innermost layer surrounding an individual Schwann cell sheath.

1. Epineurium 2. Perineurium 3. Endoneurium

What is the pia mater?

Deepest meninx that is attached directly to the surface of the spinal cord

List the functions of the spinal cord. Select all that apply. 1. It senses stimuli from the environment. 2. It produces responses through reflex mechanisms. 3. It serves as the link between the brain and the PNS. 4. It integrates incoming information.

It produces responses through reflex mechanisms. It serves as the link between the brain and the PNS. It integrates incoming information.

What are the functions of the axillary nerve? Select all that apply.

It provides sensory innervation to the shoulder joint and to the skin over part of the shoulder. It innervates the deltoid and teres minor muscles.

Identify the regions of the spinal cord. Select all that apply. 1. Lumbar 2. Inguinal 3. Cervical 4. Sacral 5. Thoracic

Lumbar Cervical Sacral Thoracic

The brachial plexus supplies nerves that function to contract which of the following?

Muscles of the arm and forearm

Identify the function of withdrawal reflexes.

Removes a body part from a painful stimulus

Identify the structures innervated by the cervical plexus. Select all that apply.

Skin of the neck Posterior portion of the head Muscles of the hyoid Diaphragm

Name the structure that serves as the link between the brain and the PNS.

Spinal cord

Explain how spinal nerves are named.

Spinal nerves are named for the region of the vertebral column from which they emerge.

Name the reflex where muscles contract in response to stretching within the muscle.

Stretch

During a spinal tap, cerebrospinal fluid is obtained from which of the following locations?

Subarachnoid space

List actions of nerves from the brachial plexus. Select all that apply.

Supply muscles acting on the scapula and arm Innervate the skin of the medial arm and forearm

What type of reflex functions to remove a body part from a painful stimulus?

Withdrawal reflex

The central canal of the spinal cord is ______.

a hollow space

The ventral and dorsal rami are branches of _____.

a spinal nerve

The ________ matter of the spinal cord consists of myelinated axons, and the ________ matter consists of neuron cell bodies.

blank 1: White blank 2: Gray

The most superficial layer of the meninges is the _____ mater and the deepest layer of the meninges is the _____ mater.

blank 1: dura blank 2: pia

Spinal nerves C5-T1 make up the __________ plexus.

brachial

The CNS consists of the ______.

brain and spinal cord

Damage to the phrenic nerve would affect one's ability to ______.

breathe

The hollow space in the center of the gray commissure of the spinal cord that helps to circulate CSF is called the ________ ________.

central canal

The muscles of the hyoid, skin of the neck, the posterior portion of the head and the diaphragm are innervated by the ________ plexus.

cervical

The phrenic nerve belongs to which nerve plexus?

cervical

The spinal cord is divided into 4 segments; they are the ________, ________ , ________ and the sacral.

cervical thoracic lumbar

The nerve plexus that innervates the muscles of the pelvic floor and the skin over the coccyx is the ______.

coccygeal plexus