Chapter 13

Question 1

What are the types of nervous systems?

Answer 1

Peripheral, somatic, central, autonomic, and afferent nervous systems.

Question 2

Which vertebrae make up the spinal cord?

Answer 2

The spinal cord is made up of cervical, thoracic, lumbar, sacral, and coccygeal vertebrae. It has 31 pairs of spinal nerves and continues to elongate until around age 4. Specialized membranes surrounding the spinal cord include the meninges.

Question 3

What nerves are associated with the shoulder and upper limbs?

Answer 3

Spinal cord nerves of the shoulder and upper limbs include the brachial plexus.

Question 4

What are coccygeal ligaments, denticulate ligaments, and spinal ligaments?

Answer 4

They are ligaments that support the spinal cord and affect its movements.

Question 5

What is the role of filum terminale?

Answer 5

The filum terminale anchors the spinal cord to the coccyx.

Question 6

What does the posterior root ganglia mainly consist of?

Answer 6

The posterior root ganglia mainly consist of sensory neuron cell bodies.

Question 7

What does the posterior root of a spinal nerve contain?

Answer 7

The posterior root contains sensory fibers. When severed, it results in loss of sensation.

Question 8

What are the three layers of the meninges?

Answer 8

Arachnoid mater, pia mater, and dura mater. The pia mater is in direct contact with the spinal cord. Cerebrospinal fluid flows in the subarachnoid space, while blood vessels run along the pia mater. CSF samples are typically obtained from the lumbar region.

Question 9

Where is the subdural space?

Answer 9

The subdural space is located between the dura mater and the arachnoid mater.

Question 10

What is meningitis?

Answer 10

Meningitis is an inflammation of the protective membranes of the brain and spinal cord, contracted through infections. Effects include fever, headache, and stiff neck.

Question 11

What is an epidural block?

Answer 11

An epidural block is a regional anesthesia that works by injecting anesthetic into the epidural space to block pain signals.

Question 12

What is the conus medullaris?

Answer 12

The conus medullaris is the tapered end of the spinal cord, found at the level of the first or second lumbar vertebra.

Question 13

What is the difference between paraplegia and quadriplegia?

Answer 13

Paraplegia is the loss of function in the lower limbs, while quadriplegia is the loss of function in all four limbs.

Question 14

What is a lumbar puncture?

Answer 14

A lumbar puncture is a procedure to collect cerebrospinal fluid, typically inserted between the third and fourth lumbar vertebrae.

Question 15

What are masses of gray matter within the central nervous system made of?

Answer 15

They are made of neuronal cell bodies.

Question 16

What are tracts, wings, horns, pyramids, and fibers?

Answer 16

Tracts are bundles of axons; wings, horns, and pyramids refer to specific structures in the spinal cord and brain. They can be microscopically seen in the central nervous system.

Question 17

How do axons in the central nervous system differ from those in the spinal cord?

Answer 17

Axons in the central nervous system are myelinated and have different regeneration capabilities compared to spinal cord axons.

Question 18

How do the gray horns of the spinal cord differ from the large anterior gray horns?

Answer 18

The gray horns contain different types of neurons and serve different functions.

Question 19

What are white columns?

Answer 19

White columns are regions of myelinated axons in the spinal cord.

Question 20

What are gray commissures and white commissures?

Answer 20

Gray commissures are areas of gray matter connecting the two sides of the spinal cord, while white commissures are areas of white matter.

Question 21

How is sensory information from visceral organs carried?

Answer 21

It is carried by visceral sensory fibers.

Question 22

What is the difference between posterior rami and anterior rami?

Answer 22

Posterior rami innervate the back, while anterior rami innervate the front and limbs.

Question 23

What is the difference between the posterior root and anterior root?

Answer 23

The posterior root contains sensory fibers, while the anterior root contains motor fibers.

Question 24

What is the term for regional loss of sensory or motor function from nerve trauma or compression?

Answer 24

The term is neuropathy.

Question 25

What is the largest peripheral nerve?

Answer 25

The sciatic nerve.

Question 26

What does loss of feeling in the thumb and first two fingers indicate?

Answer 26

It likely indicates damage to the median nerve.

Question 27

What are endoneurium, endomysium, epineurium, and epimysium?

Answer 27

Endoneurium surrounds individual nerve fibers, endomysium surrounds individual muscle fibers, epineurium surrounds entire nerves, and epimysium surrounds entire muscles.

Question 28

What is the difference between white rami communicantes and gray rami communicantes?

Answer 28

White rami communicantes carry preganglionic sympathetic fibers, while gray rami communicantes carry postganglionic sympathetic fibers.

Question 29

Where can sympathetic nerves be found?

Answer 29

Sympathetic nerves can be found in the sympathetic trunk and peripheral ganglia.

Question 30

Where do cervical, thoracic, lumbar, sacral, and coccygeal spinal nerves innervate?

Answer 30

Cervical nerves innervate the neck and upper limbs, thoracic nerves innervate the trunk, lumbar nerves innervate the lower back and legs, sacral nerves innervate the pelvis, and coccygeal nerves innervate the tailbone area.

Question 31

What is a plexus?

Answer 31

A plexus is a network of nerves. The brachial plexus receives fibers from the cervical spinal nerves and gives rise to nerves such as the median, ulnar, and radial nerves.

Question 32

Where does the ulnar nerve arise?

Answer 32

The ulnar nerve arises from the medial cord of the brachial plexus.

Question 33

What is shingles?

Answer 33

Shingles is a viral infection that affects the skin and nerves, typically in a dermatomal pattern.

Question 34

What is the perineurium?

Answer 34

The perineurium is the protective sheath surrounding a nerve fascicle.

Question 35

Where do leg muscles receive innervated spinal nerves?

Answer 35

Leg muscles receive innervated spinal nerves from the lumbar and sacral plexuses.

Question 36

Which nerves originate in the lumbar plexus?

Answer 36

Nerves such as the femoral and obturator nerves originate in the lumbar plexus. The cervical plexus originates nerves like the phrenic nerve.

Question 37

What is a dermatome?

Answer 37

A dermatome is an area of skin innervated by a specific spinal nerve.

Question 38

What are the recognized neuronal circuit patterns?

Answer 38

The recognized neuronal circuit patterns include reflex arcs, converging circuits, diverging circuits, and oscillating circuits. They differ in their function and connectivity.

Question 39

What are the different classes of reflexes?

Answer 39

Reflexes are classified as monosynaptic or polysynaptic, based on the number of synapses involved. A reflex arc is the neural pathway that mediates a reflex.

Question 40

What are the most complicated spinal reflexes?

Answer 40

The most complicated spinal reflexes include the withdrawal reflex. The Golgi tendon reflex prevents a muscle from exerting too much tension.

Question 41

What are muscle spindles?

Answer 41

Muscle spindles are sensory receptors located within muscles that detect changes in muscle length.

Question 42

What is reciprocal inhibition?

Answer 42

Reciprocal inhibition is a reflex that inhibits the antagonist muscle when the agonist muscle contracts.

Question 43

What are polysynaptic reflexes?

Answer 43

Polysynaptic reflexes involve multiple synapses and interneurons.

Question 44

What is the flexor reflex?

Answer 44

The flexor reflex is a protective withdrawal reflex. The crossed extensor reflex complements it by activating contralateral muscles.

Question 45

What are contralateral, ipsilateral, monosynaptic, involuntary, and polysynaptic reflexes?

Answer 45

Contralateral reflexes occur on the opposite side of the stimulus, ipsilateral reflexes occur on the same side, monosynaptic reflexes involve one synapse, involuntary reflexes are automatic responses, and polysynaptic reflexes involve multiple synapses.

Question 46

What can cause a reflex response to fail during a clinical exam?

Answer 46

Causes may include nerve damage, spinal cord injury, or neurological disorders.

Question 47

What does a positive Babinski reflex indicate?

Answer 47

A positive Babinski reflex indicates potential damage to the corticospinal tract in adults.