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A&P1 - Chapter 13
The Spinal Cord, Spinal Nerves and Spinal Reflexes
Question | Answer |
---|---|
The spinal cord is part the _______ nervous system. | central |
The _____ is a strand of fibrous tissue that provides longitudinal support to the spinal cord as a component of the coccygeal ligament. | filum terminale |
The spinal cord consists of four regions and _______ segments | 31 |
The dorsal root of a spinal nerve contains | axons of sensory neurons |
The ventral root of a spinal nerve contains | axons of motor neurons |
The tough, fibrous, outermost covering of the spinal cord is the | dura mater |
After age ____, the vertebral column continues to elongate, but the spinal cord itself does not. | 4 |
If the dorsal root of a spinal nerve is severed, what will happen? | sensory input would be blocked |
The layer of the meninges in direct contact with the spinal cord is the | pia meter |
A dorsal and ventral root of each spinal segment unite to form a | spinal nerve |
Describe meningitis | inflammation of the meninges occur bacteria can be the cause viruses can be the cause CSF flow can't be disrupted |
Describe an epidural block | commonly used as a method of pain control during labor and delivery, affects only the spinal nerves in the immediate area of the injection, provides sensory and motor anesthesia depending on the anesthetic selection and provide mainly sensory anesthesia |
The spinal cord continues to elongate until about the age | 4 |
Samples of CSF for diagnostic purposes are normally obtained by placing the tip of a needle in the | subarachnoid space |
Bill contracts a viral disease that destroys cells in the posterior gray horns in his spinal cord. As a result, which of the following would you expext? | loss of sensation in his torso |
The posterior horns of the spinal cord contain mainly | sensory nuclei |
The anterior horns of the spinal cord contain mainly | somatic motor nuclei |
Use Figure 13-1 The Spinal Cord Identify the structure labeled "1" | posterior white column |
Use Figure 13-1 The Spinal Cord Identify the structure labeled "4" | posterior gray horn |
Use Figure 13-1 The Spinal Cord Identify the structure labeled "10" | anterior gray commissure |
Use Figure 13-1 The Spinal Cord What is the function of the structure labeled "12"? | somatic sensory - monitor skin |
Use Figure 13-1 The Spinal Cord What is the function of the structure labeled "14"? | visceral motor - innervates organs, glands and smooth muscle |
Where do somatic motor neurons reside? | #15, somatic motor |
The outermost connective tissue covering of nerves is the | epineurium |
Muscles of the neck and shoulder are innervated by spinal nerves from the ____ region | cervical |
The ventral rami of spinal nerves C5 to T1 contribute fibers to the _____ plexus | brachial |
In the condition _____, a virus infects dorsal root ganglia, causing a painful rash whose distribution corresponds to that of the affected sensory nerves as seen in their dermatomes | shingles |
Spinal nerves from the sacral region of the cord innervate the ____ muscles | leg |
The ____ innervates the ventrolateral body surface, structures in the body wall, and the limbs | ventral ramus |
A viral disease that destroys the cells of the anterior gray horn will LEAD TO | skeletal muscle weakness or paralysis |
The complex, interwoven network formed by contributions from the central rami of neighboring spinal nerves is termed a(n) | plexus |
The central rami form four major plexuses, including all of the following EXCEPT the ____ plexus | nuchal |
If a person has a crush injury to the C3-C5 spinal segments, you would expect that he might be unable to | breathe on his own |
As the ____ nerve approaches the knee, it divides into two branches, the fibular nerve and the tibial nerve | sciatic |
Mary is in an automobile accident and suffers a spinal cord injury. She has lost feeling in her lower body. Her doctor tells her that swelling is compressing a portion of her spinal cord. Which part of her cord is likely to be compressed? | ascending tracts |
The brachial plexus gives rise to which nerves? | radial, median, ulnar and musculocutaneous - NOT phrenic |
Use Figure 13-2 Spinal Nerves Identify the structure labeled "2" | ventral ramus |
Use Figure 13-2 Spinal Nerves Identify the structure labeled "4" | white ramus |
Use Figure 13-2 Spinal Nerves Identify the structure labeled "5" | rami communicantes |
Use Figure 13-2 Spinal Nerves Identify the structure labeled "6" | sympathetic ganglion |
Use Figure 13-2 Spinal Nerves Identify the structure labeled "8" | spinal nerve |
Use Figure 13-2 Spinal Nerves What is the function of the structure labeled "12"? | innervates organs, glands and smooth muscle |
Use Figure 13-2 Spinal Nerves Which branch carries motor neurons to structures on the back of the body trunk? | #1, dorsal ramus |
Use Figure 13-2 Spinal Nerves In which structure are sensory cell bodies located? | #10, dorsal root ganglion |
You're sitting at a restaurant waiting for your food. The waiter brings a hot plate, telling you to be careful touching it. You touch it anyway, producing a pain sensation in fingers, a withdrawal of your hand, & an auditory comment of what your thinking | This represents a parallel neuronal circuit |
Describe neural reflexes | automatic motor response are the simplest form of behavior, help preserve homeostasis and involve at least two neurons |
Reflexes based on synapses formed during development are ____ reflexes | innate |
How are reflexes classified? | their development, where info processing occurs, motor response and the complexity of the neural circuit |
Describe muscle spindles | found within skeletal muscle, consists of specialized fibers called intrafusal fibers, are receptors for the stretch reflex and are innervated by gamma motor neurons |
The reflex that prevents a muscle from exerting too much tension is the ____ reflex | tendon |
The _____ reflex complements the flexor by activating contralateral muscles | crossed extendor |
What does the flexor reflex do? | moves a limb away from a painful stimulus |
In which of the following would the delay between stimulus and response be GREATER? (A) a monosynaptic reflex (B) a polysynaptic reflex | (B) a polysynaptic reflex |
Describe the characteristics of reflexes | reflexes responses can change over time, and some reflex responses can be enhances by repetition |
Tina falls while climbing a tree & lands on her back. Her frightened parents take her to the ER, where she is examined. Her knee-jerk reflex is normal and she exhibits a plantar reflex (negative Babinski reflex). Does Tina have a problem? If so, what? | suffered no damage to her spinal cord |
Describe Babinski reflex | normal in newborns, abnormal in adults, a sign of injury to descending spinal tracts and flaring of the toes when the sole is stroked |
The condition in which a person loses all feeling and movement of the arms and legs due to spinal cord injury is termed | quadriplegia |
The loss of feeling and movement of the legs is termed | paraplegia |
The ____ separates the dura mater from the walls of the vertebral canal | epidural space |
The dorsal root contains ____ neurons | sensory |
Blood vessels traveling within the ____ space deliver oxygen and nutrients to the spinal cord | subarachnoid |
During the procedure known as a(n) ____, a needle is inserted into the subarachnoid space in the inferior lumbar region | lumbar puncture |
Suppose that you feel something brushing against your abdomen. The sensory info would be carried to the spinal cord over a(n) _____ ramus | ventral |
The specific strip of skin that is innervated by a specific spinal nerve is called a | dermatome |
A complex, interwoven network of nerves is called a | plexus |
The nerve crucial for breathing that originates within the cervical plexus is called the ____ nerve | phrenic |
In ____, one neuron synapses on several postsynaptic neurons | divergence |
Interneurons are organized into functional groups called | neuronal pools |
The neural "wiring" of a single reflex is called a(n) | reflex arc |
___ reflexes activate skeletal muscles | Somatic |
The most complicated spinal reflexes are called | intersegmental reflex arcs |
A(n) ____ reflex has at least one interneuron placed between the sensory and motor neurons | polysynaptic |