Nervous Tissue

Question 1

1. Which of the following is a characteristic of neurons?
   a) Do not transmit electrical impulses
   b) Are found only in the central nervous system
   c) Have dendrites that carry impulses away from the cell body
   d) Transmit electrical impulses rapidly

Answer 1

1. d) Transmit electrical impulses rapidly
   Rationale: Neurons are specialized to transmit electrical signals quickly to ensure communication between different parts of the body.

Question 2

2. What type of neuron is most commonly found in the brain and spinal cord?
   a) Bipolar neuron
   b) Pseudounipolar neuron
   c) Multipolar neuron
   d) Sensory neuron

Answer 2

2. c) Multipolar neuron
   Rationale: Multipolar neurons are the most common type in the brain and spinal cord and have one axon and multiple dendrites.

Question 3

3. The myelin sheath in the peripheral nervous system is produced by:
   a) Schwann cells
   b) Astrocytes
   c) Microglia
   d) Oligodendrocytes

Answer 3

3. a) Schwann cells
   Rationale: In the peripheral nervous system, Schwann cells form the myelin sheath, which insulates axons and speeds up nerve conduction.

Question 4

4. Which cranial nerve supplies structures in both the head, neck, and some in the thorax and abdomen?
   a) Glossopharyngeal nerve
   b) Vagus nerve
   c) Hypoglossal nerve
   d) Trigeminal nerve

Answer 4

4. b) Vagus nerve
   Rationale: The vagus nerve (cranial nerve X) extends beyond the head and neck to supply organs in the thorax and abdomen.

Question 5

5. Explain the role of neuroglia in the nervous system.

Answer 5

5. Neuroglia support neurons by providing structural support, maintaining the environment around neurons, producing myelin, and playing a role in defense mechanisms within the CNS.

Question 6

6. Differentiate between the autonomic nervous system’s sympathetic and parasympathetic divisions.

Answer 6

6. The sympathetic division of the autonomic nervous system prepares the body for emergencies (e.g., increases heart rate and blood pressure), while the parasympathetic division is involved in energy conservation and restoration (e.g., slows heart rate and increases digestion).

Question 7

7. Describe the structure and function of the myelin sheath.

Answer 7

7. The myelin sheath is a lipid-rich layer that surrounds axons, insulates them, and increases the speed of nerve impulse transmission. In the CNS, it is formed by oligodendrocytes, and in the PNS by Schwann cells.

Question 8

8. Neurons can be classified morphologically as __________, __________, and __________ neurons based on the number of processes.

Answer 8

8. Multipolar, Bipolar, Pseudounipolar

Question 9

9. The axon hillock, a part of the neuron located adjacent to the axon, lacks __________ granules.

Answer 9

9. Nissle

Question 10

10. The blood-brain barrier is primarily maintained by __________ cells, a type of neuroglia.

Answer 10

10. Astrocyte

Question 11

11. Which of the following are true about the autonomic nervous system? (Select all that apply)
    a) It controls voluntary skeletal muscle movement.
    b) It regulates involuntary activities such as heart rate and digestion.
    c) The sympathetic division is responsible for the “fight or flight” response.
    d) It is anatomically divided into the central and peripheral nervous systems.
    e) The parasympathetic division stimulates glandular activity.

Answer 11

11. b), c), e)
    Rationale: The autonomic nervous system regulates involuntary functions (e.g., heart rate, digestion). The sympathetic division controls the “fight or flight” response, and the parasympathetic stimulates gland activity.

Question 12

12. Which of the following are classified as cranial nerves? (Select all that apply)
    a) Oculomotor nerve
    b) Vestibulocochlear nerve
    c) Trochlear nerve
    d) Hypoglossal nerve
    e) Olfactory nerve

Answer 12

12. a), b), c), d), e)
    Rationale: All listed nerves are cranial nerves that emerge from the brain and innervate various regions of the body.

Question 13

13. The neuron’s dendrites carry nerve impulses toward the cell body.
    True / False

Answer 13

13. True
    Rationale: Dendrites carry electrical impulses toward the neuron’s cell body.

Question 14

14. The neuroglia known as microglia have phagocytic properties, helping to remove damaged cells.
    True / False

Answer 14

14. True
    Rationale: Microglia act as the immune cells of the CNS, clearing debris and damaged cells.

Question 15

15. The somatic nervous system regulates activities that are under conscious control.
    True / False

Answer 15

15. True
    Rationale: The somatic nervous system controls voluntary movements, such as skeletal muscle actions.

Question 16

16. A patient presents with symptoms of severe dizziness and hearing loss in one ear. Which type of neuron and nervous system structure could be involved? Provide your reasoning.

Answer 16

16. The vestibulocochlear nerve (cranial nerve VIII) and sensory neurons in the inner ear could be involved. These neurons transmit sensory information related to balance and hearing, so dysfunction can cause dizziness and hearing loss.

Question 17

17. A patient suffers from multiple sclerosis, a disease that affects the myelin sheath of neurons. How would this impact nerve impulse conduction, and why is this clinically significant?

Answer 17

17. Multiple sclerosis affects myelin, leading to slower or disrupted nerve impulses. This can cause symptoms like muscle weakness, numbness, and coordination problems, as efficient communication between neurons is hindered.

Question 18

18. A 35-year-old male is brought into the emergency room with rapid heart rate, dilated pupils, and sweating after a car accident. Which part of his autonomic nervous system is activated, and what physiological responses are expected?

Answer 18

18. The sympathetic nervous system is activated in a “fight or flight” response, leading to increased heart rate, dilation of pupils, and sweating. This prepares the body to respond to stress or emergencies.

Question 19

19. Which of the following statements about neuroglia is true?
    a) Astrocytes are primarily responsible for myelination of axons in the peripheral nervous system.
    b) Oligodendrocytes myelinate multiple axons in the central nervous system.
    c) Schwann cells are only found in the central nervous system.
    d) Microglia are involved in neurotransmitter release.

Answer 19

19. b) Oligodendrocytes myelinate multiple axons in the central nervous system.
    Rationale: Oligodendrocytes are responsible for myelinating axons in the CNS and can extend their processes to multiple axons.

Question 20

20. Which of the following structures connects the CNS to the rest of the body?
    a) Ganglia
    b) Cranial nerves
    c) Neuroglia
    d) Peripheral nervous system

Answer 20

20. d) Peripheral nervous system
    Rationale: The peripheral nervous system connects the CNS to the rest of the body through spinal and cranial nerves.

Question 21

21. Which component of a neuron directly receives synaptic input from another neuron?
    a) Axon
    b) Telodendria
    c) Dendrites
    d) Soma

Answer 21

21. c) Dendrites
    Rationale: Dendrites receive incoming signals from other neurons at synapses.

Question 22

22. In the central nervous system, the __________ cells form the myelin sheath around axons, while __________ cells form it in the peripheral nervous system.

Answer 22

22. Oligodendrocytes, Schwann
    Rationale: Oligodendrocytes myelinate axons in the CNS, while Schwann cells myelinate in the PNS.

Question 23

23. The __________ system is responsible for controlling voluntary skeletal muscle movement, while the __________ system controls involuntary functions such as heart rate and gland secretion.

Answer 23

23. Somatic, Autonomic
    Rationale: The somatic system controls voluntary movements, while the autonomic system handles involuntary processes.

Question 24

24. The axon carries nerve impulses toward the cell body, while dendrites carry them away from the cell body.
    True / False

Answer 24

24. False
    Rationale: Axons carry impulses away from the cell body, while dendrites carry them toward the cell body.

Question 25

25. Satellite cells support neurons in the peripheral ganglia by regulating the microenvironment around them.
    True / False

Answer 25

25. True
    Rationale: Satellite cells regulate the external environment around neurons in ganglia.

Question 26

26. A 65-year-old woman is diagnosed with a tumor in her central nervous system, leading to a breakdown of the blood-brain barrier. Which neuroglial cells might be most affected, and what consequences could this have for the nervous tissue?
    (Hint: Consider the role of neuroglia in maintaining the blood-brain barrier.)

Answer 26

26. Astrocytes, as they are responsible for maintaining the blood-brain barrier. A breakdown in this barrier could result in toxins or pathogens entering the CNS, leading to further damage to neurons and neuroglia.

Question 27

27. A 40-year-old male presents with difficulty controlling fine motor movements, muscle weakness, and cognitive decline. Based on these symptoms, which part of the nervous system is most likely affected, and why? Consider both neuron structure and neuroglia involvement.

Answer 27

27. The central nervous system, particularly the motor pathways and possibly oligodendrocytes, which support myelination. Damage here could explain both motor dysfunction and cognitive decline.

Question 28

28. A patient with a spinal cord injury is unable to move their lower limbs but retains sensation. Explain which parts of the nervous system could be damaged and how motor and sensory pathways are involved.

Answer 28

28. The ventral roots of the spinal cord, which contain motor neurons, are likely damaged, leading to the inability to move. Sensory pathways (dorsal roots) may still function, allowing the patient to retain sensation.

Question 29

Match the Following
29. Match the neuroglial cell with its function:
Cell Type Function
a) Oligodendrocytes 1. Phagocytic activity during trauma
b) Astrocytes 2. Myelin production in the CNS
c) Schwann cells 3. Myelin production in the PNS
d) Microglia 4. Structural support and blood-brain barrier
e) Ependymal cells 5. Involved in the secretion of cerebrospinal fluid

Answer 29

29. a) 2
    b) 4
    c) 3
    d) 1
    e) 5

Question 30

30. Explain how the node of Ranvier facilitates faster transmission of nerve impulses.

Answer 30

30. The nodes of Ranvier are gaps in the myelin sheath that allow for saltatory conduction, where the nerve impulse “jumps” from one node to the next, speeding up transmission.

Question 31

31. Compare the roles of sensory (afferent) neurons and motor (efferent) neurons in the nervous system. How do these neurons work together during a reflex action, such as pulling your hand away from a hot object?

Answer 31

31. Sensory neurons carry signals from receptors (e.g., in the skin) to the CNS. Motor neurons carry the response signal from the CNS to muscles or glands. In a reflex action, sensory neurons quickly communicate with motor neurons, often via interneurons, to trigger a fast response (like moving away from heat).

Question 32

32. A professional athlete experiences a spinal cord injury during a game and loses control of their lower body. Which specific part of the spinal nerve is likely damaged if only motor control is affected? Provide reasoning based on your knowledge of spinal nerve anatomy.

Answer 32

32. Damage to the ventral root of the spinal nerve is likely, as it contains motor fibers that control muscle movements. If only motor control is affected, the sensory fibers (dorsal root) may remain intact.

Question 33

33. A research scientist is developing a drug that targets oligodendrocytes to enhance myelination in patients with multiple sclerosis. Why would targeting oligodendrocytes in the CNS be a focus of therapy for this condition?

Answer 33

33. Oligodendrocytes are the cells responsible for myelination in the CNS. In diseases like multiple sclerosis, myelin is degraded, so enhancing the function or protection of oligodendrocytes can help restore proper nerve signal transmission.

Question 34

Select All That Apply
34. Which of the following are true about the classification of neurons based on function?
a) Sensory neurons transmit impulses from receptors to the CNS.
b) Motor neurons carry impulses from the CNS to muscles and glands.
c) Interneurons only exist in the peripheral nervous system.
d) Most interneurons are multipolar neurons.

Answer 34

34. a), b), d)
    Rationale: Sensory neurons transmit information toward the CNS, motor neurons carry it away, and most interneurons are found in the CNS and are multipolar.

Question 35

35. Which of the following are involved in forming a synapse between neurons? (Select all that apply)
    a) Axon terminals (telodendria)
    b) Dendrites
    c) Axon hillock
    d) Synaptic vesicles

Answer 35

35. a), b), d)
    Rationale: Axon terminals, dendrites, and synaptic vesicles are involved in forming and transmitting signals across synapses.

Question 36

36. The point at which an axon terminates and transfers the nerve impulse to another cell is called the __________.

Answer 36

36. Synapse

Question 37

37. The __________ nervous system prepares the body for emergencies by increasing heart rate and blood pressure, while the __________ nervous system promotes “rest and digest” functions like slowing the heart rate.

Answer 37

37. Sympathetic, Parasympathetic

Question 38

38. A patient presents with altered heart rate, digestive disturbances, and pupil dilation after a traumatic event. Which divisions of the nervous system are likely involved, and how does the body’s response reflect the balance between these systems?

Answer 38

38. The sympathetic nervous system is activated after the traumatic event, causing physiological responses such as increased heart rate and pupil dilation. The parasympathetic system, which would normally balance these functions, is overridden during the stress response.

Question 39

39. Which of the following best explains how the nervous system maintains homeostasis?
    a) By directly regulating hormone secretion from endocrine glands
    b) By integrating information from sensory organs and coordinating a response via motor neurons
    c) By generating electrical impulses in muscles to promote digestion
    d) By stimulating osteoclasts to maintain bone integrity

Answer 39

39. b) By integrating information from sensory organs and coordinating a response via motor neurons.
    Rationale: The nervous system processes sensory input and sends out motor commands to maintain homeostasis, such as adjusting heart rate and respiration.

Question 40

40. Which cells are primarily responsible for cleaning up cellular debris following injury to the nervous system?
    a) Schwann cells
    b) Microglia
    c) Astrocytes
    d) Satellite cells

Answer 40

40. b) Microglia
    Rationale: Microglia are the immune cells of the central nervous system, responsible for phagocytosing debris following neural injury.

Question 41

41. The __________ nervous system is divided into the sympathetic and parasympathetic divisions, which often have opposite effects on organs they innervate.

Answer 41

41. Autonomic
    Rationale: The autonomic nervous system controls involuntary functions and is divided into sympathetic and parasympathetic divisions, which often have opposing actions.

Question 42

42. Synaptic vesicles are located in the __________ of the neuron and are responsible for storing __________, which are released during synaptic transmission.

Answer 42

42. Axon terminal, neurotransmitters
    Rationale: Synaptic vesicles are found in the axon terminal, where they release neurotransmitters during synaptic transmission.

Question 43

43. The vagus nerve is part of the sympathetic nervous system and only affects the heart and digestive system.
    True / False

Answer 43

43. False
    Rationale: The vagus nerve is part of the parasympathetic nervous system and has broader effects, including control of heart rate, digestive processes, and other organ functions.

Question 44

44. The dorsal root ganglion contains cell bodies of sensory neurons.
    True / False

Answer 44

44. True
    Rationale: The dorsal root ganglion houses the cell bodies of sensory neurons, which relay sensory information from the body to the CNS.

Question 45

45. A 30-year-old patient has suffered a traumatic brain injury, and imaging shows extensive damage to the motor cortex. How would this impact their ability to control muscle movements, and what symptoms might you expect to see based on the injury location?

Answer 45

45. Damage to the motor cortex will impair voluntary movement control. The patient may present with paralysis or weakness (hemiplegia or hemiparesis) on the opposite side of the body, depending on the extent and location of the damage.

Question 46

46. A patient comes in with severe weakness in their legs but has normal sensation. You suspect a demyelinating disease that only affects the motor neurons. Explain the likely pathophysiology and how this correlates with the symptoms.

Answer 46

46. The demyelination of motor neurons would slow or disrupt the conduction of nerve impulses to muscles, leading to muscle weakness while sensory neurons remain unaffected. This correlates with the patient’s difficulty in moving their legs but normal sensation.

Question 47

47. A 28-year-old woman reports increased heart rate, sweating, and rapid breathing during public speaking events. What part of her autonomic nervous system is likely overactive, and what specific physiological responses are contributing to her symptoms?

Answer 47

47. Her sympathetic nervous system is likely overactive, triggering a “fight or flight” response. Physiological responses such as increased heart rate, sweating, and rapid breathing occur due to increased sympathetic stimulation.

Question 48

Matching
48. Match the neuron type with its primary function:
Neuron Type Function
a) Sensory neuron 1. Transmits signals from CNS to muscles
b) Motor neuron 2. Connects sensory and motor pathways
c) Interneuron 3. Carries signals from receptors to the CNS

Answer 48

48. a) 3
    b) 1
    c) 2

Question 49

49. How do Schwann cells and oligodendrocytes differ in their role in myelination, and what would be the consequence of a defect in each cell type?

Answer 49

49. Schwann cells myelinate axons in the PNS, while oligodendrocytes myelinate in the CNS. A defect in Schwann cells would affect peripheral nerve conduction (e.g., in conditions like Guillain-Barré Syndrome), while a defect in oligodendrocytes would slow CNS nerve conduction (e.g., multiple sclerosis).

Question 50

50. Describe how the nervous system interacts with the cardiovascular system during exercise. How do the sympathetic and parasympathetic divisions balance the body’s needs in response to physical exertion?

Answer 50

50. During exercise, the nervous system increases heart rate and dilates blood vessels to supply muscles with oxygen-rich blood via sympathetic activation. After exercise, the parasympathetic system helps slow heart rate and restore normal function. This balance ensures proper cardiovascular response to changing body needs.

Question 51

51. Imagine you are designing a drug to improve nerve regeneration after injury. Which specific cells and structures of the nervous system would you target, and why? Provide an explanation that considers the role of myelination, axon growth, and synaptic connections.

Answer 51

51. To enhance nerve regeneration, I would target Schwann cells and oligodendrocytes for myelination support, as well as promote axonal growth via growth factors that enhance synaptic connections and axon extension. Encouraging remyelination is crucial for restoring nerve conduction.

Question 52

52. Which of the following are true about myelinated and unmyelinated neurons? (Select all that apply)
    a) Myelinated neurons transmit nerve impulses faster than unmyelinated neurons.
    b) Nodes of Ranvier are absent in unmyelinated neurons.
    c) Myelinated neurons are only found in the central nervous system.
    d) Schwann cells myelinate axons in the peripheral nervous system.

Answer 52

52. a), b), d)
    Rationale: Myelinated neurons conduct impulses more quickly because of the saltatory conduction at nodes of Ranvier. Unmyelinated neurons lack these nodes. Schwann cells myelinate peripheral axons.

Question 53

53. A 50-year-old patient has been diagnosed with Guillain-Barré Syndrome, an autoimmune disorder that affects the peripheral nervous system by damaging the myelin sheaths. What symptoms would you expect to see, and why? How would this condition differ from multiple sclerosis, which primarily affects the central nervous system?

Answer 53

53. Symptoms of Guillain-Barré Syndrome include muscle weakness, numbness, and possible paralysis. This differs from multiple sclerosis (MS) because MS affects the central nervous system, whereas Guillain-Barré primarily affects the peripheral nervous system. In MS, patients often experience coordination problems, vision issues, and cognitive symptoms, which are less common in Guillain-Barré.

Question 54

54. Which of the following is NOT a function of the nervous system?
    o a) React to stimuli.
    o b) Conduct impulses to organs.
    c) Transport oxygen to tissues.
    d) Integrate the activity of different body parts

Answer 54

54. c) Transport oxygen to tissues.
    Rationale: The nervous system is responsible for communication and control within the body, not for transporting oxygen. This is a function of the circulatory system.

Question 55

55. The central nervous system is responsible for:
    o a) Connecting the CNS to the rest of the body.
    o b) Regulating activities that are involuntary.
    o c) Processing information and sending nerve impulses that control bodily movements.
    o d) Providing sensory and motor innervation to all parts of the body, except for the viscera, smooth muscle, and glands.

Answer 55

55. c) Processing information and sending nerve impulses that control bodily movements.
    Rationale: The central nervous system, consisting of the brain and spinal cord, is the primary processing center for information, coordinating bodily movements based on sensory input and internal signals.

Question 56

56. Which type of neuron transmits motor information from the CNS to effectors?
    o a) Sensory neurons
    o b) Motor neurons
    o c) Interneurons

Answer 56

56. b) Motor neurons
    Rationale: Motor neurons, also known as efferent neurons, are responsible for transmitting motor commands from the CNS to muscles and glands, initiating actions.

Question 57

57. Which of the following is a characteristic of a multipolar neuron?
    o a) One axon and one dendrite
    o b) Situated in the retina of the eyeball
    o c) One axon and many dendrites
    o d) Situated in the spinal (dorsal root) ganglia

Answer 57

57. c) One axon and many dendrites
    Rationale: Multipolar neurons are characterized by a single axon that transmits signals and multiple dendrites that receive signals from other neurons, enabling complex integration of information.

Question 58

58. Which part of a neuron is responsible for protein synthesis?
    o a) Neurofibrils
    o b) Nissle granules
    o c) Axon hillock
    o d) Axolemma

Answer 58

58. b) Nissle granules
    Rationale: Nissle granules, which are dense clusters of ribosomes and rough endoplasmic reticulum, are responsible for protein synthesis within neurons, essential for maintaining cellular function and producing neurotransmitters.

Question 59

59. Which type of glial cell is responsible for forming the myelin sheath in the peripheral nervous system?
    o a) Astrocytes
    o b) Schwann cells
    o c) Oligodendrocytes
    o d) Microglia

Answer 59

59. b) Schwann cells
    Rationale: Schwann cells are a type of glial cell in the PNS that form the myelin sheath around axons, providing insulation and speeding up nerve impulse conduction.

Question 60

60. Which cranial nerve is responsible for carrying sensory information related to smell?
    o a) Optic nerve
    o b) Olfactory nerve
    o c) Facial nerve
    o d) Vagus nerve

Answer 60

60. b) Olfactory nerve
    Rationale: The olfactory nerve is responsible for transmitting sensory information from the olfactory receptors in the nose to the brain, allowing us to perceive smell.

Question 61

61. The spinal nerves are named according to:
    o a) Their function.
    o b) The region of the spinal cord they are attached to.
    o c) The number of axons they contain.
    o d) The type of neurons they are composed of.

Answer 61

61. b) The region of the spinal cord they are attached to.
    Rationale: Spinal nerves are named based on the segment of the spinal cord they originate from, such as cervical, thoracic, lumbar, sacral, and coccygeal nerves, reflecting their location along the vertebral column.

Question 62

62. What is the function of the dorsal root of a spinal nerve?
    o a) Carries motor fibers leaving the spinal cord.
    o b) Carries sensory fibers entering the spinal cord.
    o c) Supplies the muscles and skin of the back.
    o d) Connects to the sympathetic ganglia.

Answer 62

62. b) Carries sensory fibers entering the spinal cord.
    Rationale: The dorsal root of a spinal nerve carries sensory information from the body to the spinal cord, where it can be processed or relayed to the brain.

Question 63

63. Which of the following structures contains pseudounipolar neurons?
    o a) Sensory ganglia
    o b) Autonomic ganglia
    o c) Gray rami communicantes
    o d) White rami communicantes

Answer 63

63. a) Sensory ganglia
    Rationale: Sensory ganglia contain the cell bodies of pseudounipolar neurons, which are responsible for transmitting sensory information from the periphery to the central nervous system.

Question 64

64. Nervous tissue is made up of neurons and neuroglia. (True/False)

Answer 64

64. True
    Rationale: Nervous tissue is composed of two main cell types: neurons, which transmit electrical signals, and neuroglia, which provide support and protection for neurons.

Question 65

65. The autonomic nervous system regulates activities that are under conscious control, such as moving skeletal muscles. (True/False)

Answer 65

65. False
    Rationale: The autonomic nervous system controls involuntary actions, such as regulating heart rate, digestion, and breathing, while the somatic nervous system controls voluntary movements of skeletal muscles.

Question 66

66. Neuroglia transmit electrical impulses faster than neurons. (True/False)

Answer 66

66. False
    Rationale: Neurons are specialized for transmitting electrical impulses, while neuroglia support and protect neurons but do not transmit impulses themselves.

Question 67

67. Interneurons are the most common type of neuron. (True/False)

Answer 67

67. True
    Rationale: Interneurons, which connect sensory and motor neurons within the CNS, are the most abundant type of neuron, enabling complex processing and integration of information.

Question 68

68. Myelinated neurons conduct nerve impulses slower than unmyelinated neurons. (True/False)

Answer 68

68. False
    Rationale: Myelinated neurons, with their insulating myelin sheath, conduct impulses much faster than unmyelinated neurons, as the signal jumps between the nodes of Ranvier.

Question 69

69. Ependymal cells are involved in the secretion of cerebrospinal fluid.(True/False)

Answer 69

69. True
    Rationale: Ependymal cells, lining the ventricles of the brain and central canal of the spinal cord, are responsible for producing and circulating cerebrospinal fluid, which cushions and protects the CNS.

Question 70

70. A nerve trunk is surrounded by a connective tissue sheath called the endoneurium.(True/False)

Answer 70

70. False
    Rationale: A nerve trunk is surrounded by the epineurium, while individual nerve fibers within a fascicle are surrounded by the endoneurium. The perineurium surrounds each fascicle within a nerve.

Question 71

71. The ventral rami of all thoracic spinal nerves are connected to sympathetic ganglia by gray and white rami communicantes. (True/False)

Answer 71

71. True
    Rationale: The ventral rami of thoracic and upper lumbar spinal nerves connect to the sympathetic ganglia via both gray and white rami communicantes, facilitating communication between the CNS and the sympathetic nervous system.

Question 72

72. The parasympathetic nervous system prepares the body for an emergency by increasing heart rate and constricting blood vessels. (True/False)

Answer 72

72. False
    Rationale: The sympathetic nervous system prepares the body for “fight or flight” responses, while the parasympathetic nervous system promotes “rest and digest” functions, slowing heart rate and increasing digestive activity.

Question 73

73. Autonomic ganglia contain cell bodies of multipolar neurons. (True/False)

Answer 73

73. True
    Rationale: Autonomic ganglia, which relay signals between the CNS and the autonomic nervous system, contain the cell bodies of multipolar neurons that control involuntary functions.

Question 74

74. Describe the difference between the somatic and autonomic nervous systems.

Answer 74

74. The somatic nervous system controls voluntary movements of skeletal muscles, while the autonomic nervous system regulates involuntary functions like heart rate, digestion, and breathing.
    The somatic nervous system involves conscious control, while the autonomic nervous system operates without conscious awareness.

Question 75

75. Explain the functions of the three types of neurons: sensory neurons, motor neurons, and interneurons.

Answer 75

75. Sensory neurons (afferent) transmit sensory information from receptors in the body to the CNS. Motor neurons (efferent) carry motor commands from the CNS to muscles and glands. Interneurons connect sensory and motor neurons within the CNS, enabling communication and information processing.
    Sensory neurons detect stimuli, motor neurons initiate actions, and interneurons mediate between them.

Question 76

76. Describe the structure of a myelinated axon, including the roles of Schwann cells, the myelin sheath, and nodes of Ranvier.

Answer 76

76. A myelinated axon is wrapped by Schwann cells, which form the myelin sheath, an insulating layer composed of phospholipids. The myelin sheath is interrupted at intervals by nodes of Ranvier.
    The myelin sheath speeds up nerve impulse conduction by allowing the signal to jump between nodes, a process called saltatory conduction.

Question 77

77. What are the main functions of astrocytes in the nervous system?

Answer 77

77. Astrocytes provide structural support for neurons, contribute to the blood-brain barrier, regulate the chemical environment around neurons, and help repair damaged nervous tissue.
    They play a crucial role in maintaining the homeostasis of the CNS and protecting neurons from harmful substances.

Question 78

78. Compare and contrast the structure and function of sensory and autonomic ganglia.

Answer 78

78. Sensory ganglia contain the cell bodies of pseudounipolar neurons and are involved in transmitting sensory information to the CNS. Autonomic ganglia contain the cell bodies of multipolar neurons and relay signals between the CNS and the autonomic nervous system.
    Sensory ganglia are associated with sensory nerves, while autonomic ganglia are part of the autonomic nervous system.

Question 79

79. The part of a neuron that carries nerve impulses away from the cell body is called the ____________.

Answer 79

79. Axon

Question 80

80. _____________ are small, spine-like projections on the dendrites of neurons that make synaptic connections with other neurons.

Answer 80

80. Dendritic spines

Question 81

81. The connective tissue sheath that surrounds an individual nerve fiber within a fascicle is called the ____________.

Answer 81

81. Endoneurium

Question 82

82. The ____________ nerve is the 10th cranial nerve and supplies structures in the head, neck, thorax, and abdomen.

Answer 82

82. Vagus

Question 83

83. The ____________ root of a spinal nerve contains motor fibers that leave the spinal cord.

Answer 83

83. Ventral

Question 84

84. Which of the following are functions of the peripheral nervous system?
    o a) Connects the CNS to the rest of the body.
    o b) Processes information and sends nerve impulses to control bodily movements.
    o c) Includes cranial nerves and spinal nerves.
    o d) Regulates activities that are involuntary.

Answer 84

84. a) Connects the CNS to the rest of the body., c) Includes cranial nerves and spinal nerves., d) Regulates activities that are involuntary.

Question 85

85. Which of the following are characteristics of the sympathetic nervous system?
    o a) Prepares the body for an emergency.
    o b) Increases heart rate.
    o c) Reduces heart rate.
    o d) Constricts peripheral blood vessels.
    o e) Increases peristalsis of the intestinal tract.

Answer 85

85. a) Prepares the body for an emergency., b) Increases heart rate., d) Constricts peripheral blood vessels.

Question 86

86. Which of the following cell types are considered neuroglia?
    o a) Neurons
    o b) Astrocytes
    o c) Schwann cells
    o d) Oligodendrocytes
    o e) Microglia

Answer 86

86. b) Astrocytes, c) Schwann cells, d) Oligodendrocytes, e) Microglia

Question 87

87. A patient presents with weakness and numbness in their right arm and leg. An MRI reveals a lesion in the left side of the brain, specifically affecting the motor cortex. Explain why a lesion on the left side of the brain would cause symptoms on the right side of the body.

Answer 87

87. The motor pathways in the brain cross over (decussate) at the level of the medulla oblongata. This means that the left side of the brain controls the right side of the body, and vice versa. Therefore, a lesion on the left side of the brain, affecting the motor cortex, would result in motor deficits on the right side of the body.
    This is a fundamental principle of neuroanatomy that explains why damage to one side of the brain often manifests as symptoms on the opposite side of the body.