hw 14

In which structure are sensory cell bodies located?

10

What is the significance of the cauda equina?

It is made up of extensions of the posterior and anterior roots of spinal segments L2 to S5. It forms as the vertebral column continues to elongate after growth of the spinal cord ceases at about age 4.

Part complete Which is correct regarding the spinal cord?

The adult spinal cord ends between vertebrae L1 and L2.

Tina falls while climbing a tree and lands on her back. Her frightened parents take her to the emergency room, where she is examined. Her knee-jerk reflex is normal and she exhibits a plantar reflex (negative Babinski reflex). These results suggest that

Tina suffered no damage to her spinal cord.

A person with polio has lost the use of his leg muscles. In which area of his spinal cord would you expect the virus-infected motor neurons to be?

anterior gray horns

Identify the structure labeled "2."

anterior ramus

Of the spinal meninges, the middle one is the ________ mater.

arachnoid

All of the following are true of muscle spindles except that they

are found in tendons

The anterior root of a spinal nerve contains

axons of motor neurons

Describe the composition of the gray matter of the spinal cord.

cell bodies of neurons, neuroglia, and unmyelinated axons

The posterior root ganglia mainly contain

cell bodies of sensory neurons

spinal nerves

contain both sensory and motor.

What is the function of the structure labeled "14"?

control of autonomic effectors

What is the function of the structure labeled "15"?

control of skeletal muscle

The tough, fibrous, outermost covering of the spinal cord is the

dura mater

Which is the innermost connective tissue layer of the spinal nerve that surrounds each axon?

endoneurium

The ________ is a strand of fibrous tissue that provides longitudinal support as a component of the coccygeal ligament.

filum terminale

Enlargements of the spinal cord occur

in those spinal segments that control the limbs

There are five steps in the typical reflex arc. Which of the following best describes the activity of the third step?

information processing within the CNS

In a(n) ________ reflex, a sensory neuron synapses directly on a motor neuron.

monosynaptic

Damage to which nerve of the cervical plexus would interfere with the ability to breathe?

phrenic nerve

The ________ of each spinal nerve innervates the skin and muscles of the back.

posterior ramus

In the condition ________, a virus infects posterior root ganglia, causing a painful rash whose distribution corresponds to that of the affected sensory nerves as seen in their dermatomes.

shingles

Compared to the vertebral column, the spinal cord is

shorter

What is the function of the structure labeled "12"?

somatic sensory receiving

Identify the structure labeled "8."

spinal nerve

Where is spinal CSF located?

subarachnoid space