CH 13 Spinal Cord and Spinal Nerves

The nerve plexus innervates the pectoral girdle and upper limbs?

Brachial plexus

Which nerve of the cervical plexus innervates 5 extrinsic muscles of the larynx?

Ansa cervicalis

Which spinal segment of the cervical plexus innervates the skin of the upper chest, shoulder, neck, and ear?

C2-C3

The brachial plexus consists of which spinal nerve segments?

C5-T1

The __________ consists of the brain and spinal cord.

CNS

Regarding the gross anatomy of the spinal cord, which of the following structures supplies/supply nerves to the pectoral girdle?

Cervical enlargement

The distribution of the sensory fibers within which of the following structures illustrates the segmental division of dermatomes supplied by the spinal cord?

Dorsal and ventral rami

Which nerve of the brachial plexus supplies the rhomboid and levator scapulae muscles?

Dorsal scapular nerve

The __________ is the outermost covering of the spinal cord and brain.

Dura matter

Which of the spinal meninges consist(s) of a layer of dense irregular connective tissue with an epithelial covering on both inner and outer surfaces?

Dura matter

Which connective tissue covering of a peripheral nerve is a central layer composed of collagenous fibers, elastic fibers, and fibrocytes, and divides the nerve into a series of fascicles?

Perineurium

Which nerve of the cervical plexus is extremely important, in that it innervates the diaphragm?

Phrenic nerve

Where are the denticulate ligaments located?

Pia mater

Which layer of the spinal meninges is the innermost layer, and is firmly bound to the underlying neural tissue?

Pia mater

Which structure of the spinal cord contains somatic and visceral sensory nuclei?

Posterior (dorsal) gray horn

Which nerve of the sacral plexus innervates the skin of the perineum and posterior surface of the thigh and leg?

Posterior femoral cutaneous nerve

Which white matter columns are between the posterior gray horns and the posterior median sulcus?

Posterior white columns

Which nerve of the sacral plexus is the largest nerve in the human body, innervates the semimembranosus and semitendinosus muscles, and branches into the tibial and fibular nerves?

Sciatic nerve

stretch reflex

- It provides automatic regulation of skeletal muscle length. - It responds to information provided by the stretch receptors of muscle spindles. - It is a simple monosynaptic reflex.

Which of the following describes the filum terminale?

- It begins at the inferior tip of the conus medullaris. - It extends from the conus medullaris along the length of the vertebral canal as far as the dorsum of the coccyx. - It is a slender strand of fibrous tissue.

plexuses

- They form during development as small skeletal muscles fuse with their neighbors to form larger muscles with compound origins. - They include the cervical, brachial, lumbar, and sacral plexuses. - where ventral rami are converging and branching to form these compound nerves.

Visceral (autonomic) reflexes control the actions of all of the following.

- glands - smooth muscles - cardiac muscles

All of the following are true of the spinal cord and associated structures.

- the entire spinal cord is divided into 31 segments. - the spinal nerves associated with the spinal cord are classified as mixed nerves. - after age 4, the spinal cord does not grow.

true of the sectional anatomy of the spinal cord

- the gray matter surrounds the central canal. - the spinal cord contains a central H-shaped mass of gray matter. - the anterior median fissure and posterior median sulcus follow the division between the left and right sides of the spinal cord. - white matter contains large numbers of myelinated and unmyelinated axons organized in tracts and columns

order the following steps of a neural (withdrawal) reflex.

1. Arrival of stimulus and activation of the receptor 2. Activation of a sensory neuron 3. Information processing in the CNS 4. Activation of a motor neuron 5. Response by effector

spinal nerve plexus

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

order the following steps of a stretch reflex

1. Stimulus 2. Activation of sensory neuron 3. Information processing at a motor neuron 4. Activation of motor neuron 5. Response

How many pairs of spinal nerves are associated with the cervical vertebrae?

8

Which structure of the spinal cord contains axons crossing from one end of the cord to the other before reaching a destination within the gray matter?

Gray commissure

the following structure of the rami communicantes that supplies postganglionic fibers to smooth muscles and glands of the body wall and limbs?

Gray ramus

What are the projections of gray matter toward the outer surface of the spinal cord called?

Horns

Which nerve of the lumbar plexus is responsible for supplying the abdominal muscles (external and internal obliques and transversus abdominis) and the skin over the inferior abdomen and buttocks?

Iliohypogastric nerve

Where is cerebrospinal fluid found?

In the subarachnoid space

Which nerve of the sacral plexus innervates the large gluteus maximus muscle?

Inferior gluteal nerve

Which type of reflexes is genetically determined?

Innate reflexes

Which gray horns contain neurons concerned with somatic motor control?

Interior gray horns

Spinal contusion

It is a hemorrhage occurring in the meninges and within the spinal cord as a result of whiplash or falls.

The adult spinal cord extends from the foramen magnum to the inferior border of the __________.

L1 Vertebra

Which structure of the spinal cord is only found between segments T1 and L2, and contains visceral motor neurons?

Lateral (intermediate) gray horns

Which nerve of the brachial plexus innervates the serratus anterior muscle?

Long thoracic nerve

What is the correct description of a spinal injury called paraplegia?

Loss of motor control in the lower limbs

Which nerve of the lumbar plexus innervates the adductor muscles of the hip, gracilis muscle, and skin over the medial surface of the thigh?

Obturator nerve

an example of a reflex classification based on the nature of the resulting motor response?

Somatic or visceral (autonomic) reflexes

The arachnoid mater consists of simple squamous epithelium and is separated from the pia mater by which of the following?

Subarachnoid space