Nervous System Practice Questions

109 multiple-choice questions on Nervous system for paramedic and EMT students, from Chapter 8 (Anatomy and Physiology). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

109 practice questions

1. What are the two main divisions of the nervous system?

   1. A. Somatic and autonomic
   2. B. Central and peripheral
   3. C. Sympathetic and parasympathetic
   4. D. Sensory and motor
   Show answer

   Answer: B. Central and peripheral

   The CNS is the brain and spinal cord. The PNS is all the nerves outside them.

2. The autonomic nervous system controls:

   1. A. Conscious sensations such as touch and pain
   2. B. Spinal reflexes of skeletal muscle only
   3. C. Involuntary functions such as heart rate
   4. D. Voluntary movement of skeletal muscle
   Show answer

   Answer: C. Involuntary functions such as heart rate

   It also controls digestion. The autonomic system has sympathetic and parasympathetic branches. The somatic system controls voluntary movement.

3. The part of a neuron that carries impulses away from the cell body is the:

   1. A. Axon
   2. B. Dendrite
   3. C. Synapse
   4. D. Myelin
   Show answer

   Answer: A. Axon

   Axons carry impulses away from the cell body; dendrites carry them toward it.

4. The myelin sheath:

   1. A. Produces neurotransmitters for the synapse
   2. B. Insulates the axon to speed conduction
   3. C. Connects the axon of one neuron to another
   4. D. Stores calcium for impulse transmission
   Show answer

   Answer: B. Insulates the axon to speed conduction

   Impulses jump between the nodes of Ranvier. Demyelinating diseases like MS slow conduction.

5. Depolarization of a nerve or muscle cell occurs when:

   1. A. Sodium rushes into the cell
   2. B. Chloride enters the cell
   3. C. Potassium rushes into the cell
   4. D. Calcium leaves the cell
   Show answer

   Answer: A. Sodium rushes into the cell

   Sodium entering makes the inside of the cell positive. Repolarization happens as potassium moves out.

6. The junction between two neurons is the:

   1. A. Node of Ranvier
   2. B. Synapse
   3. C. Ganglion
   4. D. Axon hillock
   Show answer

   Answer: B. Synapse

   Neurotransmitters carry the signal across the synaptic cleft.

7. Which structure connects the left and right cerebral hemispheres?

   1. A. Thalamus
   2. B. Pons
   3. C. Corpus callosum
   4. D. Cerebral aqueduct
   Show answer

   Answer: C. Corpus callosum

   The corpus callosum is a thick band of nerve fibers that lets the hemispheres communicate.

8. Voluntary motor function, personality, and judgment are controlled by the:

   1. A. Frontal lobe
   2. B. Temporal lobe
   3. C. Occipital lobe
   4. D. Parietal lobe
   Show answer

   Answer: A. Frontal lobe

   Frontal lobe injury can change a patient's behavior and impulse control.

9. Vision is processed in the:

   1. A. Frontal lobe
   2. B. Occipital lobe
   3. C. Temporal lobe
   4. D. Parietal lobe
   Show answer

   Answer: B. Occipital lobe

   The occipital lobe is at the back of the head. A blow there can cause visual disturbances.

10. Hearing and much of memory and language comprehension are processed in the:

    1. A. Cerebellum
    2. B. Frontal lobe
    3. C. Temporal lobe
    4. D. Occipital lobe
    Show answer

    Answer: C. Temporal lobe

    The temporal lobe sits at the side of the head, near the ears.

11. The cerebellum is primarily responsible for:

    1. A. Long-term memory storage
    2. B. Speech and language production
    3. C. Balance and coordination
    4. D. Vision and visual memory
    Show answer

    Answer: C. Balance and coordination

    Cerebellar problems cause ataxia (an unsteady gait) and poor coordination.

12. Which brainstem structure controls breathing, heart rate, and blood pressure?

    1. A. Cerebellum
    2. B. Medulla oblongata
    3. C. Midbrain tectum
    4. D. Pons
    Show answer

    Answer: B. Medulla oblongata

    Herniation that compresses the medulla leads to respiratory and cardiac failure.

13. The hypothalamus regulates:

    1. A. Voluntary movement and speech
    2. B. Body temperature, thirst, and hunger
    3. C. Balance and fine motor coordination
    4. D. Visual and auditory processing
    Show answer

    Answer: B. Body temperature, thirst, and hunger

    It also controls pituitary function, linking the nervous and endocrine systems.

14. The reticular activating system (RAS) is responsible for:

    1. A. Consciousness and arousal
    2. B. Hormone release from the pituitary
    3. C. Hearing and speech comprehension
    4. D. Balance and coordination
    Show answer

    Answer: A. Consciousness and arousal

    Damage to the RAS or to both hemispheres causes a decreased level of consciousness.

15. The limbic system is mainly involved in:

    1. A. Vision and visual field processing
    2. B. Breathing rate and rhythm
    3. C. Muscle tone and coordination
    4. D. Emotion, behavior, and memory
    Show answer

    Answer: D. Emotion, behavior, and memory

    The limbic system plays a large part in emotional and behavioral responses.

16. What is the order of the meninges, from outermost to innermost?

    1. A. Dura, pia, arachnoid
    2. B. Dura, arachnoid, pia
    3. C. Arachnoid, dura, pia
    4. D. Pia, arachnoid, dura
    Show answer

    Answer: B. Dura, arachnoid, pia

    Dura, arachnoid, pia. Mnemonic: DAP. Epidural and subdural bleeds are named by their location relative to the dura.

17. Cerebrospinal fluid is produced mainly by the:

    1. A. Dura mater
    2. B. Pituitary gland
    3. C. Spinal cord
    4. D. Choroid plexus
    Show answer

    Answer: D. Choroid plexus

    The choroid plexus in the ventricles makes CSF, which cushions and nourishes the brain.

18. The blood-brain barrier:

    1. A. Produces cerebrospinal fluid in the ventricles
    2. B. Limits what enters the brain from blood
    3. C. Cushions the brain against the skull
    4. D. Controls heart rate and blood pressure
    Show answer

    Answer: B. Limits what enters the brain from blood

    It protects the brain, but it also limits which medications can reach it.

19. In adults, the spinal cord ends at approximately:

    1. A. T6
    2. B. L1-L2
    3. C. The coccyx
    4. D. S1
    Show answer

    Answer: B. L1-L2

    Below L1-L2 the nerve roots continue as the cauda equina.

20. How many pairs of cranial nerves are there?

    1. A. 33
    2. B. 12
    3. C. 10
    4. D. 31
    Show answer

    Answer: B. 12

    There are 12 pairs, numbered I through XII.

21. How many pairs of spinal nerves are there?

    1. A. 31
    2. B. 12
    3. C. 33
    4. D. 24
    Show answer

    Answer: A. 31

    There are 31 pairs: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal.

22. The vagus nerve is cranial nerve:

    1. A. III
    2. B. VII
    3. C. IX
    4. D. X
    Show answer

    Answer: D. X

    CN X is the main parasympathetic nerve to the heart, lungs, and gut. Vagal stimulation slows the heart.

23. The phrenic nerve, which controls the diaphragm, arises from:

    1. A. C7-T1
    2. B. C3-C5
    3. C. L1-L2
    4. D. T1-T2
    Show answer

    Answer: B. C3-C5

    "C3, 4, 5 keeps the diaphragm alive." A high cervical injury can stop breathing.

24. A dermatome is:

    1. A. A sensory branch of a cranial nerve
    2. B. Skin area supplied by one spinal nerve
    3. C. A layer of the dermis below the epidermis
    4. D. A chronic inflammatory skin disease
    Show answer

    Answer: B. Skin area supplied by one spinal nerve

    Dermatome maps help find the level of a spinal injury.

25. Which dermatome is at the level of the umbilicus?

    1. A. T10
    2. B. T12
    3. C. C5
    4. D. L1
    Show answer

    Answer: A. T10

    T4 is at the nipple line and T10 at the umbilicus.

26. A reflex arc:

    1. A. Is processed entirely within the brain
    2. B. Is processed at the spinal cord level
    3. C. Involves only the cranial nerves
    4. D. Always requires conscious thought
    Show answer

    Answer: B. Is processed at the spinal cord level

    It travels through the spinal cord and responds before the brain processes the signal. This is why you pull your hand from a hot stove before you feel the pain.

27. Stimulating the sympathetic nervous system causes:

    1. A. Decreased heart rate and bronchoconstriction
    2. B. Increased heart rate and bronchodilation
    3. C. Decreased blood glucose and slowed heart
    4. D. Increased digestion and pupil constriction
    Show answer

    Answer: B. Increased heart rate and bronchodilation

    Fight or flight: a faster, stronger heart, dilated airways and pupils, and more glucose available.

28. The main neurotransmitter of the parasympathetic nervous system is:

    1. A. Dopamine
    2. B. Norepinephrine
    3. C. Acetylcholine
    4. D. Serotonin
    Show answer

    Answer: C. Acetylcholine

    The parasympathetic system is cholinergic ("rest and digest"). Atropine blocks it.

29. Stimulating beta-1 receptors causes:

    1. A. Peripheral arteriole vasoconstriction
    2. B. Increased heart rate and force
    3. C. Bronchial smooth muscle relaxation
    4. D. Pupil constriction and tearing
    Show answer

    Answer: B. Increased heart rate and force

    Beta-1 affects the heart (you have 1 heart). Beta-2 affects the lungs (you have 2 lungs).

30. Stimulating beta-2 receptors causes:

    1. A. Decreased glucose
    2. B. Vasoconstriction
    3. C. Increased heart rate only
    4. D. Bronchodilation
    Show answer

    Answer: D. Bronchodilation

    This is how albuterol works.

31. Stimulating alpha-1 receptors causes:

    1. A. Peripheral vasoconstriction
    2. B. Increased renal urine output
    3. C. Slowing of the heart rate
    4. D. Bronchial smooth muscle relaxation
    Show answer

    Answer: A. Peripheral vasoconstriction

    Alpha-1 constricts vessels and raises blood pressure.

32. The light-sensitive layer at the back of the eye is the:

    1. A. Retina
    2. B. Cornea
    3. C. Lens
    4. D. Iris
    Show answer

    Answer: A. Retina

    The retina contains the rods and cones. A retinal detachment is an emergency.

33. Balance and equilibrium are sensed by the:

    1. A. Cochlea
    2. B. Semicircular canals
    3. C. Tympanic membrane
    4. D. Eustachian tube
    Show answer

    Answer: B. Semicircular canals

    The semicircular canals in the inner ear sense balance. The cochlea handles hearing.

34. The central nervous system consists of the:

    1. A. Brain and cranial nerves
    2. B. Brain and spinal cord
    3. C. Spinal cord and spinal nerves
    4. D. Autonomic nerves
    Show answer

    Answer: B. Brain and spinal cord

    Everything else is peripheral.

35. The peripheral nervous system includes:

    1. A. The spinal cord and meninges
    2. B. The brain and brainstem
    3. C. The ventricles and CSF
    4. D. Cranial and spinal nerves
    Show answer

    Answer: D. Cranial and spinal nerves

    It carries information to and from the CNS. It includes the cranial and spinal nerves and all their branches.

36. The somatic nervous system controls:

    1. A. Voluntary skeletal muscle
    2. B. Glandular secretion
    3. C. Heart rate and contractility
    4. D. Digestion and peristalsis
    Show answer

    Answer: A. Voluntary skeletal muscle

    It also carries conscious sensation. It controls voluntary skeletal muscle movement.

37. Afferent nerves carry impulses:

    1. A. From the CNS to glands
    2. B. Only within the brain itself
    3. C. Toward the CNS (sensory)
    4. D. Away from the CNS to muscles
    Show answer

    Answer: C. Toward the CNS (sensory)

    Efferent nerves carry motor commands outward. Afferent nerves carry sensory information toward the CNS.

38. Efferent nerves carry impulses:

    1. A. Toward sensory receptors
    2. B. Away from the CNS to effectors
    3. C. Toward the brain from receptors
    4. D. Within the spinal cord only
    Show answer

    Answer: B. Away from the CNS to effectors

    Motor is efferent; sensory is afferent. Efferent nerves carry impulses away from the CNS to effectors, the muscles and glands.

39. Dendrites function to:

    1. A. Release neurotransmitters into the cleft
    2. B. Carry impulses away from the cell body
    3. C. Insulate the axon to speed conduction
    4. D. Carry impulses toward the cell body
    Show answer

    Answer: D. Carry impulses toward the cell body

    A neuron may have many dendrites. Dendrites receive impulses and carry them toward the cell body.

40. The neuron cell body is also called the:

    1. A. Axon
    2. B. Soma
    3. C. Synapse
    4. D. Terminal
    Show answer

    Answer: B. Soma

    It contains the nucleus.

41. Nodes of Ranvier are:

    1. A. Clusters of nerve cell bodies
    2. B. Junctions between two neurons
    3. C. Vesicles storing neurotransmitter
    4. D. Gaps in the myelin sheath
    Show answer

    Answer: D. Gaps in the myelin sheath

    Impulses jump between them. These gaps speed conduction.

42. Schwann cells produce myelin in the:

    1. A. Brain only
    2. B. Spinal cord only
    3. C. Central nervous system
    4. D. Peripheral nervous system
    Show answer

    Answer: D. Peripheral nervous system

    Oligodendrocytes do so in the CNS.

43. Neurotransmitters are stored in:

    1. A. Vesicles at the axon terminals
    2. B. Dendritic spines of the receiving cell
    3. C. Myelin sheath around the axon
    4. D. The nucleus of the cell body
    Show answer

    Answer: A. Vesicles at the axon terminals

    They are released into the synaptic cleft.

44. Repolarization of a neuron occurs as:

    1. A. Potassium moves out of the cell
    2. B. Chloride flows out of the cell
    3. C. Calcium flows into the cell
    4. D. Sodium rushes into the cell
    Show answer

    Answer: A. Potassium moves out of the cell

    The sodium-potassium pump restores the gradients. Potassium leaving restores the negative interior.

45. The refractory period is the time when:

    1. A. The neuron cannot be stimulated again
    2. B. The neuron fires repeatedly on its own
    3. C. Neurotransmitters are being synthesized
    4. D. Myelin regenerates along the axon
    Show answer

    Answer: A. The neuron cannot be stimulated again

    It limits maximum firing rate.

46. The largest part of the brain is the:

    1. A. Cerebrum
    2. B. Diencephalon
    3. C. Brainstem
    4. D. Cerebellum
    Show answer

    Answer: A. Cerebrum

    It handles conscious thought, sensation, and voluntary movement.

47. The parietal lobe is primarily responsible for:

    1. A. Processing visual input
    2. B. Processing touch and pain
    3. C. Processing sound and hearing
    4. D. Coordinating balance
    Show answer

    Answer: B. Processing touch and pain

    It also handles spatial orientation. The parietal lobe processes sensation such as touch, temperature, and pain.

48. Broca area, involved in speech production, is usually located in the:

    1. A. Right parietal lobe
    2. B. Cerebellum
    3. C. Right occipital lobe
    4. D. Left frontal lobe
    Show answer

    Answer: D. Left frontal lobe

    Damage causes expressive aphasia.

49. Wernicke area, involved in understanding language, is located in the:

    1. A. Occipital lobe
    2. B. Brainstem
    3. C. Temporal lobe
    4. D. Frontal lobe
    Show answer

    Answer: C. Temporal lobe

    Damage causes receptive aphasia.

50. The thalamus functions primarily as:

    1. A. A sensory relay to the cortex
    2. B. A hormone-secreting gland
    3. C. The respiratory control center
    4. D. The primary motor center
    Show answer

    Answer: A. A sensory relay to the cortex

    Almost all sensory input passes through it.

51. The hypothalamus regulates all of the following EXCEPT:

    1. A. Voluntary movement
    2. B. Thirst and hunger
    3. C. Pituitary hormone release
    4. D. Temperature
    Show answer

    Answer: A. Voluntary movement

    It is the main homeostatic control center.

52. The brainstem consists of the:

    1. A. Cerebrum, cerebellum, and thalamus
    2. B. Medulla and spinal cord only
    3. C. Pons and cerebellum only
    4. D. Midbrain, pons, and medulla
    Show answer

    Answer: D. Midbrain, pons, and medulla

    It controls the most basic life functions.

53. The pons contributes to:

    1. A. Releasing pituitary hormones
    2. B. Processing visual signals
    3. C. Regulating breathing patterns
    4. D. Controlling digestion
    Show answer

    Answer: C. Regulating breathing patterns

    It works with the medulla's respiratory centers. The pons helps regulate breathing and relays signals between brain regions.

54. The midbrain is involved in:

    1. A. Expressive speech production
    2. B. Peristalsis and digestion
    3. C. Visual and auditory reflexes
    4. D. Blood pressure control only
    Show answer

    Answer: C. Visual and auditory reflexes

    It contains part of the reticular activating system. The midbrain handles visual and auditory reflexes and contributes to level of consciousness.

55. Cerebrospinal fluid functions to:

    1. A. Carry oxygen to neurons
    2. B. Block toxins from entering the brain
    3. C. Cushion the brain and cord
    4. D. Drain venous blood from the brain
    Show answer

    Answer: C. Cushion the brain and cord

    It circulates through ventricles and around the cord. CSF cushions the brain and spinal cord and provides nutrients. Blocking toxins is the job of the blood-brain barrier, and venous blood drains through the dural sinuses, not the CSF.

56. The dura mater is:

    1. A. A large venous sinus
    2. B. The innermost meningeal layer
    3. C. The tough outer meningeal layer
    4. D. The inner table of the skull
    Show answer

    Answer: C. The tough outer meningeal layer

    Epidural bleeding occurs above it.

57. The pia mater:

    1. A. Adheres to the brain surface
    2. B. Is a thick avascular sheet
    3. C. Is the middle meningeal layer
    4. D. Lines the inner skull
    Show answer

    Answer: A. Adheres to the brain surface

    It follows every contour of the brain.

58. The subarachnoid space contains:

    1. A. Venous blood only
    2. B. Epidural fat pads
    3. C. Cerebrospinal fluid
    4. D. Lymphatic fluid
    Show answer

    Answer: C. Cerebrospinal fluid

    A ruptured aneurysm bleeds into it.

59. The brain uses what proportion of the body's oxygen at rest?

    1. A. About 5 percent
    2. B. About 50 percent
    3. C. About 2 percent
    4. D. About 20 percent
    Show answer

    Answer: D. About 20 percent

    It has minimal reserve and depends on constant flow.

60. The brain's only usable fuel under normal circumstances is:

    1. A. Glucose
    2. B. Protein
    3. C. Fat
    4. D. Ketones alone
    Show answer

    Answer: A. Glucose

    It cannot store significant amounts.

61. Cerebral perfusion pressure is determined by:

    1. A. Respiratory rate and depth
    2. B. MAP minus intracranial pressure
    3. C. Systolic pressure alone
    4. D. Heart rate times stroke volume
    Show answer

    Answer: B. MAP minus intracranial pressure

    Rising ICP reduces perfusion unless pressure rises. CPP equals mean arterial pressure minus intracranial pressure.

62. The spinal cord's central gray matter contains:

    1. A. Nerve cell bodies
    2. B. Only sensory fibers
    3. C. Myelinated tracts
    4. D. Cerebrospinal fluid
    Show answer

    Answer: A. Nerve cell bodies

    White matter contains myelinated tracts.

63. Ascending tracts of the spinal cord carry:

    1. A. Sensory information to the brain
    2. B. Reflex signals back to muscles
    3. C. Motor commands to muscles
    4. D. Autonomic output to organs
    Show answer

    Answer: A. Sensory information to the brain

    Descending tracts carry motor signals.

64. The cauda equina consists of:

    1. A. The lower spinal cord itself
    2. B. Nerve roots below the cord's end
    3. C. The meninges of the sacrum
    4. D. The fused sacral vertebrae
    Show answer

    Answer: B. Nerve roots below the cord's end

    It resembles a horse's tail. It is the bundle of nerve roots extending below the end of the spinal cord.

65. A spinal nerve is formed from:

    1. A. A single mixed root
    2. B. Dorsal and ventral roots joined
    3. C. Branches of the cranial nerves
    4. D. Ventral motor fibers only
    Show answer

    Answer: B. Dorsal and ventral roots joined

    Each supplies a dermatome and myotome. The dorsal root is sensory and the ventral root is motor.

66. Cranial nerve II is the:

    1. A. Olfactory nerve
    2. B. Oculomotor nerve
    3. C. Optic nerve
    4. D. Trigeminal nerve
    Show answer

    Answer: C. Optic nerve

    It carries vision.

67. Cranial nerve VII is the:

    1. A. Trigeminal nerve
    2. B. Facial nerve
    3. C. Hypoglossal nerve
    4. D. Vagus nerve
    Show answer

    Answer: B. Facial nerve

    It controls facial expression and taste.

68. Pupil constriction is controlled by which cranial nerve?

    1. A. VII
    2. B. II
    3. C. III
    4. D. V
    Show answer

    Answer: C. III

    The oculomotor nerve is compressed in herniation.

69. A blown pupil on one side in a head-injured patient suggests:

    1. A. Isolated direct eye injury
    2. B. Normal anatomic variation
    3. C. Oculomotor nerve compression
    4. D. Hypoglycemic brain injury
    Show answer

    Answer: C. Oculomotor nerve compression

    It is an ominous finding. Rising intracranial pressure compresses the oculomotor nerve.

70. The sympathetic nervous system originates from which spinal segments?

    1. A. Cranial and sacral
    2. B. Thoracic and lumbar
    3. C. Sacral only
    4. D. Cervical only
    Show answer

    Answer: B. Thoracic and lumbar

    It is called the thoracolumbar division.

71. The parasympathetic nervous system originates from:

    1. A. Thoracic and lumbar segments
    2. B. Cranial nerves and sacral cord
    3. C. Lumbar segments only
    4. D. Cervical cord segments only
    Show answer

    Answer: B. Cranial nerves and sacral cord

    It is called the craniosacral division.

72. Which effect is parasympathetic?

    1. A. Bronchodilation
    2. B. Pupil dilation
    3. C. Increased salivation
    4. D. Increased heart rate
    Show answer

    Answer: C. Increased salivation

    It is the rest-and-digest system. Parasympathetic tone increases salivation and digestion.

73. Sympathetic stimulation of sweat glands causes:

    1. A. No change in sweating
    2. B. Increased sweating
    3. C. Vasodilation without sweat
    4. D. Dry, flushed skin
    Show answer

    Answer: B. Increased sweating

    Sweat glands are the exception that uses acetylcholine.

74. The adrenal medulla is essentially part of which system?

    1. A. Central
    2. B. Parasympathetic
    3. C. Somatic
    4. D. Sympathetic
    Show answer

    Answer: D. Sympathetic

    It extends the fight-or-flight response. It releases epinephrine and norepinephrine into the blood.

75. Weeks after a complete T4 spinal cord injury, tapping the patellar tendon still makes the leg kick. Why?

    1. A. The brain still controls the leg through other tracts
    2. B. The injury must be incomplete
    3. C. The reflex arc is completed at the lumbar cord without the brain
    4. D. Reflexes are produced by the muscle alone
    Show answer

    Answer: C. The reflex arc is completed at the lumbar cord without the brain

    A deep tendon reflex travels from a sensory neuron to a synapse in the cord segment (L2-L4 for the knee) and back out a motor neuron. The brain is not needed. Once spinal shock resolves, reflexes below a complete injury return and are often brisk. A reflex does not prove the injury is incomplete, and the muscle cannot complete the arc alone.

76. The Babinski reflex in an adult is:

    1. A. A normal finding
    2. B. An upper motor neuron sign
    3. C. A sign of muscle disease
    4. D. A lower motor neuron sign
    Show answer

    Answer: B. An upper motor neuron sign

    It is normal in infants. In an adult it is abnormal and suggests an upper motor neuron problem.

77. Deep tendon reflexes are used to assess:

    1. A. Joint range of motion
    2. B. Peripheral circulation
    3. C. Spinal reflex arc integrity
    4. D. Muscle strength and bulk
    Show answer

    Answer: C. Spinal reflex arc integrity

    Absent reflexes may indicate cord injury. They test the integrity of nerve pathways at specific spinal levels.

78. Autonomic dysreflexia occurs in patients with:

    1. A. Acute ischemic brainstem stroke
    2. B. Diabetic peripheral neuropathy
    3. C. Spinal cord injury at or above T6
    4. D. Any closed head injury
    Show answer

    Answer: C. Spinal cord injury at or above T6

    A distended bladder is a common trigger. A stimulus below the injury triggers severe hypertension.

79. The reticular activating system is located in the:

    1. A. Frontal lobe
    2. B. Spinal cord
    3. C. Brainstem
    4. D. Cerebellum
    Show answer

    Answer: C. Brainstem

    It maintains wakefulness.

80. Decorticate posturing involves:

    1. A. Flaccid, limp extremities
    2. B. Arms flexed, legs flexed
    3. C. Arms flexed, legs extended
    4. D. Arms and legs extended
    Show answer

    Answer: C. Arms flexed, legs extended

    It indicates injury above the brainstem. The arms flex toward the core.

81. Decerebrate posturing involves:

    1. A. Arms and legs extended
    2. B. Arms flexed, legs extended
    3. C. Flaccid, limp extremities
    4. D. Arms and legs flexed
    Show answer

    Answer: A. Arms and legs extended

    It suggests deeper, more serious brainstem injury. The arms are also rotated inward.

82. Some IV antibiotics reach the CSF poorly at normal doses when treating meningitis. The anatomic reason is:

    1. A. CSF flows too fast to hold the drug in the brain
    2. B. The meninges have no blood supply of their own
    3. C. Tight junctions of the blood-brain barrier limit entry
    4. D. The brain has no capillaries for drugs to cross
    Show answer

    Answer: C. Tight junctions of the blood-brain barrier limit entry

    Brain capillaries have tight junctions and support from astrocytes, forming the blood-brain barrier, which keeps out many drugs and toxins. Inflamed meninges let somewhat more through. CSF turns over slowly, the meninges are vascular, and the brain is richly supplied with capillaries.

83. The sense of smell is carried by cranial nerve:

    1. A. I
    2. B. V
    3. C. II
    4. D. VIII
    Show answer

    Answer: A. I

    The olfactory nerve is the first cranial nerve.

84. Hearing and balance are carried by cranial nerve:

    1. A. X
    2. B. V
    3. C. VII
    4. D. VIII
    Show answer

    Answer: D. VIII

    The vestibulocochlear nerve serves both.

85. The trigeminal nerve is responsible for:

    1. A. Facial expression muscles
    2. B. Hearing and balance
    3. C. Facial sensation and chewing
    4. D. Swallowing and gag reflex
    Show answer

    Answer: C. Facial sensation and chewing

    It has three branches.

86. The hypoglossal nerve controls:

    1. A. Tongue movement
    2. B. Facial expression
    3. C. Eye movement
    4. D. Swallowing
    Show answer

    Answer: A. Tongue movement

    Tongue deviation suggests injury to it.

87. Sympathetic stimulation causes pupils to:

    1. A. Dilate
    2. B. Accommodate for near vision
    3. C. Constrict
    4. D. Lose the light reflex
    Show answer

    Answer: A. Dilate

    Parasympathetic stimulation constricts them. Accommodation for near vision includes pupil constriction, a parasympathetic action. Sympathetic stimulation does not abolish the light reflex.

88. The cornea, iris, and lens are structures of the:

    1. A. Eye
    2. B. Retina
    3. C. Uvea
    4. D. Inner ear
    Show answer

    Answer: A. Eye

    The iris controls pupil size. The retina is the light-sensitive inner layer of the eye and does not contain the cornea or lens. The uvea includes the iris but not the cornea or lens. The inner ear holds the cochlea and semicircular canals.

89. Aqueous humor is found:

    1. A. In the middle ear
    2. B. In the brain ventricles
    3. C. Behind the lens
    4. D. In the anterior chamber
    Show answer

    Answer: D. In the anterior chamber

    Vitreous humor fills the posterior chamber.

90. The eardrum is properly called the:

    1. A. Tympanic membrane
    2. B. Cochlea
    3. C. Auditory canal
    4. D. Oval window
    Show answer

    Answer: A. Tympanic membrane

    It transmits sound to the ossicles.

91. The eustachian tube connects the:

    1. A. Middle ear and nasopharynx
    2. B. Inner ear and brain
    3. C. Outer ear and middle ear
    4. D. Nasal cavity and sinuses
    Show answer

    Answer: A. Middle ear and nasopharynx

    It equalizes pressure.

92. Taste and smell are considered:

    1. A. Balance senses
    2. B. Mechanical senses
    3. C. Chemical senses
    4. D. Visual senses
    Show answer

    Answer: C. Chemical senses

    Both detect dissolved or airborne chemicals.

93. Proprioception refers to:

    1. A. Sense of body position
    2. B. Sense of temperature
    3. C. Awareness of pain
    4. D. Sense of fine touch
    Show answer

    Answer: A. Sense of body position

    It relies on receptors in muscles and joints. It includes awareness of body position and movement.

94. A neurotransmitter that inhibits nervous system activity is:

    1. A. Epinephrine
    2. B. GABA
    3. C. Dopamine only
    4. D. Norepinephrine
    Show answer

    Answer: B. GABA

    Benzodiazepines enhance its effect.

95. Dopamine is associated with:

    1. A. Gastric acid secretion
    2. B. Movement control and reward
    3. C. Pain transmission in the cord
    4. D. Muscle contraction at the endplate
    Show answer

    Answer: B. Movement control and reward

    It also acts on vascular receptors. Dopamine also affects mood; deficiency is seen in Parkinson disease.

96. Serotonin influences:

    1. A. Mood, sleep, and appetite
    2. B. Skeletal muscle contraction
    3. C. Heart rate and contractility
    4. D. Gastric acid secretion only
    Show answer

    Answer: A. Mood, sleep, and appetite

    Serotonin syndrome results from excess activity.

97. Acetylcholine's roles include:

    1. A. Sleep regulation in the pineal gland
    2. B. Skeletal muscle and vagal signaling
    3. C. Sensory transmission in the dorsal horn
    4. D. Alpha-receptor vasoconstriction
    Show answer

    Answer: B. Skeletal muscle and vagal signaling

    Organophosphates block its breakdown. It activates skeletal muscle and carries parasympathetic transmission.

98. Glucose deprivation affects the brain by:

    1. A. Little effect, since the brain can burn fat
    2. B. Delayed changes, buffered by brain glycogen
    3. C. Rapid confusion and seizures
    4. D. Gradual, mild changes only
    Show answer

    Answer: C. Rapid confusion and seizures

    Check glucose in every altered patient. Prolonged deprivation causes permanent injury. The brain cannot use fatty acids directly and stores very little glycogen, so a fall in glucose affects it within minutes.

99. Increased intracranial pressure initially produces:

    1. A. Bradycardia and hypertension
    2. B. Irregular respirations
    3. C. Hypotension and tachycardia
    4. D. Headache, vomiting, altered LOC
    Show answer

    Answer: D. Headache, vomiting, altered LOC

    Cushing triad is a late sign. Early signs include changes in level of consciousness.

100. Autoregulation of cerebral blood flow means:

     1. A. Flow is fixed regardless of demand
     2. B. Flow depends on heart rate alone
     3. C. Vessels adjust to keep flow steady
     4. D. Flow varies directly with blood pressure
     Show answer

     Answer: C. Vessels adjust to keep flow steady

     Injury can impair this ability. Steady flow is kept across a range of pressures.

101. A seizure represents:

     1. A. Reduced, slowed brain activity
     2. B. Excessive abnormal electrical discharge
     3. C. A transient drop in cerebral blood flow
     4. D. A primary disorder of muscle fibers
     Show answer

     Answer: B. Excessive abnormal electrical discharge

     Causes range from epilepsy to hypoglycemia.

102. The postictal state is characterized by:

     1. A. Fixed, dilated pupils and apnea
     2. B. Confusion and drowsiness
     3. C. Lucid interval then sudden coma
     4. D. Ongoing convulsive activity
     Show answer

     Answer: B. Confusion and drowsiness

     It may last minutes to hours. It is the period of confusion and drowsiness after a seizure. Fixed, dilated pupils with apnea suggest herniation or arrest, not a routine postictal state. A lucid interval followed by coma is the classic pattern of an epidural hematoma.

103. Peripheral neuropathy commonly produces:

     1. A. Expressive aphasia and dysarthria
     2. B. Recurrent generalized seizures
     3. C. Gradual loss of central vision
     4. D. Distal numbness and tingling
     Show answer

     Answer: D. Distal numbness and tingling

     Diabetes is a leading cause. Weakness of the extremities is also common.

104. Multiple sclerosis involves:

     1. A. Autoimmune joint inflammation
     2. B. Myelin damage in the CNS
     3. C. Wasting of muscle fibers only
     4. D. Progressive loss of bone density
     Show answer

     Answer: B. Myelin damage in the CNS

     Symptoms vary with the areas affected.

105. Aging of the nervous system is associated with:

     1. A. Faster reflex responses
     2. B. Improved short-term memory
     3. C. An increase in neuron count
     4. D. Slowed reaction time
     Show answer

     Answer: D. Slowed reaction time

     Baseline function varies widely among individuals. Brain mass and sensory acuity also decline.

106. Which structure connects the brainstem to the spinal cord?

     1. A. Medulla oblongata
     2. B. Cerebellum
     3. C. Thalamus
     4. D. Corpus callosum
     Show answer

     Answer: A. Medulla oblongata

     Herniation through that opening is fatal. The medulla continues through the foramen magnum.

107. Damage to the spinal cord above C3 to C5 is critical because it:

     1. A. Spares all respiratory muscles
     2. B. Affects sensation but not motor
     3. C. Paralyzes only the lower limbs
     4. D. Can paralyze the diaphragm
     Show answer

     Answer: D. Can paralyze the diaphragm

     The phrenic nerve arises from those levels. Breathing may stop.

108. Neurogenic shock differs from other shock states by:

     1. A. Producing tachycardia and pale skin
     2. B. Causing cold, clammy skin
     3. C. Hypotension without tachycardia
     4. D. Producing severe hypertension
     Show answer

     Answer: C. Hypotension without tachycardia

     Loss of sympathetic tone is the cause. Skin is typically warm and dry.

109. Which is the correct pathway of a sensory impulse?

     1. A. Muscle, motor neuron, spinal cord, brain
     2. B. Brain, spinal cord, sensory neuron, receptor
     3. C. Receptor, sensory neuron, cord, brain
     4. D. Brain, spinal cord, motor neuron, muscle
     Show answer

     Answer: C. Receptor, sensory neuron, cord, brain

     Interpretation occurs in the cortex.