B3M1 Flashcards

1
Q

From which of the following landmarks does the scalp extend from anteriorly?
A. The temporal lines
B. The external occipital protuberance
C. The superciliary arches
D. The superior nuchal lines

A

C. The superciliary arches

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2
Q

Which artery ascends in front of the auricle and divides into anterior and posterior
branches?
A. Occipital artery
B. Superficial temporal artery
C. Posterior auricular artery
D. Supratrochlear artery

A

B. Superficial temporal artery

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3
Q

Which nerve accompanies the occipital artery as it ascends to the scalp?
A. Supratrochlear nerve
B. Supraorbital nerve
C. Greater occipital nerve
D. Lesser occipital nerve

A

C. Greater occipital nerve

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4
Q

Which of the following do the supratrochlear and supraorbital veins form when they
unite?
A. Facial vein
B. Retromandibular vein
C. External jugular vein
D. Maxillary vein

A

A. Facial vein

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5
Q

Which of the following forms the dura mater?
A. The external layer of the primordial meninges
B. The internal layer of the primordial meninges
C. The neural tube
D. The subarachnoid space

A

A. The external layer of the primordial meninges

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6
Q

What might be the consequence of a damaged or weakened meningeal septa on the
brain during high-speed movements?
A. Reduced overall brain stability
B. Potential disruption in neural signaling pathways, leading to reduced nerve
efficiency and coordination
C. Greater susceptibility to brain displacement
D. Altered blood flow dynamics within the cranial compartments

A

C. Greater susceptibility to brain displacement

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7
Q

To which structure is the anterior end of the falx cerebri attached?
A. The occipital bone
B. The internal frontal crest and crista galli
C. The petrous part of the temporal bone
D. The anterior clinoid processes

A

B. The internal frontal crest and crista galli

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8
Q

Which of the following describes the tentorial notch?
A. A sinus within the tentorium cerebelli
B. The intersection between the falx cerebri and falx cerebelli
C. The point where the straight sinus begins
D. A gap for the passage of the midbrain

A

D. A gap for the passage of the midbrain

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9
Q

Stimulation of dural sensory endings below the tentorium cerebelli produces referred
pain to which of the following areas?
A. The face and forehead
B. The vertex
C. The back of the neck
D. The lower back

A

C. The back of the neck

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9
Q

Which of the following describes best the diaphragma sellae?
A. It separates the cerebral hemispheres
B. It forms the roof of the sella turcica
C. It allows the passage of the optic nerves
D. It forms the floor of the cranial cavity

A

B. It forms the roof of the sella turcica

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10
Q

What organelle is noticeably absent in the Axon Hillock?
A. Nucleus
B. Lysosome
C. Nissl bodies
D. Microtubules

A

C. Nissl bodies

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11
Q

Which type of neuron do interneurons belong to?
A. Golgi Type I
B. Golgi Type II
C. Golgi Type III
D. Golgi Type IV

A

B. Golgi Type II

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12
Q

Where are the cell bodies of interneurons in the central nervous systems
located?
A. Dorsal root ganglion
B. Cranial nerve ganglion
C. Spinal ganglion
D. Terminal ganglion

A

A. Dorsal root ganglion

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13
Q

Which of the following correctly describes the structural differences between
axons and dendrites?
A. Dendrites are single branched, while axons are highly branched
B. Dendrites are myelinated, while axons are unmyelinated
C. Dendrites arborize near the soma, while axons branch at synapse
D. Dendrites have Golgi apparatus, while Axons do not contain one

A

C. Dendrites arborize near the soma, while axons branch at synapse

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14
Q

Neurons can be classified based on the number of processes extending from
their cell body. Which of the following is an example of a multipolar neuron?
A. Sensory neuron in the dorsal root ganglia
B. Motor neuron in the anterior spinal horn
C. Photoreceptor in the retinal ganglion
D. Afferent neuron in the spiral ganglion

A

B. Motor neuron in the anterior spinal horn

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15
Q

Which of the following best describes the role of dendrites in impulse
conduction?
A. Dendrites conduct impulses away from the cell body toward other neurons.
B. Dendrites are covered by a myelin sheath to speed up impulse transmission.
C. Dendrites receive incoming signals and conduct impulses toward the soma.
D. Dendrites tend to arborize by the synaptic terminal as terminal boutons

A

C. Dendrites receive incoming signals and conduct impulses toward the soma.

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16
Q

While examining a spinal cord slide, a medical student notices a neuron with
abundant granular material near its nucleus. To confirm the student’s suspicion that
these are Nissl bodies, which staining technique is used to confirm it?
A. Hematoxylin and eosin stain
B. Periodic Acid-Schiff stain
C. Cresyl violet-thionine stain
D. Gomori methenamine silver stain

A

C. Cresyl violet-thionine stain

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17
Q

Which of the following does NOT indicate high level of neuronal anabolic activity?
A. Nucleus is euchromatic
B. Nucleolus is large
C. Golgi apparatus is prominent
D. Nissl bodies are absent

A

D. Nissl bodies are absent

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18
Q

This forms the sides and roof of the cranium and articulate with each other in the
midline at the sagittal suture:
A. Frontal bone
B. Parietal bones
C. Occipital bone
D. Temporal bone

A

B. Parietal bones

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19
Q

This is also known as the thinnest part of the lateral wall of the skull, where the
anteroinferior corner of the parietal bone articulates with the greater wing of the
sphenoid:
A. Pterion
B. Bregma
C. Zygoma
D. Mandible

A

A. Pterion

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20
Q

This suture separates the parietal and temporal bones from the occipital bone:
A. Sagittal suture
B. Bregma
C. Lambdoid suture
D. Coronal suture

A

C. Lambdoid suture

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21
Q

Which of the following is correctly paired according to the boundaries of the orbital
margin?
A. Medially: zygomatic bone
B. Inferiorly: process of maxilla
C. Laterally: frontal bone
D. Inferiorly: maxilla

A

D. Inferiorly: maxilla

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22
Q

Which of the following is correctly paired with their appropriate number of vertebrae?
A. Cervical: 5
B. Sacral: 4
C. Thoracic: 10
D. Lumbar: 5

A

D. Lumbar: 5

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23
Q

Which of the following is a key structural component of nervous tissue that provides
support and insulation to neurons?
A. Osteocytes
B. Neuroglia
C. Myocytes
D. Fibroblasts

A

B. Neuroglia

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24
Q

How does a typical thoracic vertebra differ from a lumbar vertebra?
A. The body is small and broad; the spines are small and bifid
B. The body is medium size and heart-shaped; the spines are long and inclined
downward
C. The body is large and kidney-shaped; the spinous processes are short and flat
D. The vertebral foramina are triangular

A

B. The body is medium size and heart-shaped; the spines are long and inclined
downward

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25
Q

Which of the following is a primary component of nervous tissue responsible for
transmitting electrical impulses?
A. Neurons
B. Osteocytes
C. Myocytes
D. Chondrocytes

A

A. Neurons

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26
Q

Which of the following properties is considered a vital protoplasmic property of
nervous tissue, essential for its function in communication and control?
A. Conductivity
B. Contractility
C. Plasticity
D. Resilience

A

A. Conductivity

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27
Q

Which of the following best describes a primary function of nervous tissue?
A. Generating movement through contraction
B. Transmitting electrical impulses to communicate information
C. Storing minerals and providing structural support
D. Producing hormones for regulation of body processes

A

B. Transmitting electrical impulses to communicate information

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28
Q

Which of the following is a slowly-acting neurotransmitter with more prolonged and
potent actions?
A. Amines
B. Amino acids
C. Acetylcholine
D. Neuropeptides

A

D. Neuropeptides

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29
Q

Acidosis brings about which of the following?
A. Depresses neuronal activity
B. Increases neuronal excitability
C. Cerebral epileptic seizures
D. No change in neuronal activity

A

A. Depresses neuronal activity

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30
Q

This/These is/are called Effectors:
A. Eyes
B. Free nerve endings
C. Pacinian Corpuscle
D. Pituitary gland

A

D. Pituitary gland

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31
Q

Associated with the Spinal Cord level of CNS function is / are the following:
A. Walking movements
B. Control of Equilibrium
C. Memory
D. Wakefulness

A

A. Walking movements

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32
Q

Which part of the neuron is most commonly affected in retrograde nerve
degeneration?
A. Dendrite
B. Cell body
C. Axon terminals
D. Myelin sheath

A

B. Cell body

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33
Q

What cellular change typically occur in the nerve cell body in retrograde nerve
degeneration?
A. Chromatolysis
B. Apoptosis
C. Schwann cell proliferation
D. Necrosis

A

A. Chromatolysis

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34
Q

Wallerian degeneration occurs when which part of the neuron is damaged?
A. Some
B. Dendrites
C. Axon
D. Myelin sheath

A

C. Axon

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35
Q

Which cells play an important role in clearing the debris during wallerian
degeneration in the PNS?
A. Astrocytes
B. Microglia
C. Ependymal cells
D. Schwann cells

A

D. Schwann cells

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36
Q

Which ion is essential for the release of acetylcholine from the pre-synaptic
terminals thereby enhancing neuromuscular transmission?
A. Sodium
B. Potassium
C. Calcium
D. Chloride

A

C. Calcium

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37
Q

Synaptic Fatigue occurs due to:
A. Exhaustion of the stores of transmitter substances in the pre synaptic terminals
B. Progressive activation of many of the post-synaptic membrane receptors
C. Rapid development of abnormal concentration of ions inside the presynaptic
neuronal cell
D. Overflow of information from sensory receptors

A

A. Exhaustion of the stores of transmitter substances in the pre synaptic terminals

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38
Q

To which adult structure would the mesencephalon be transformed to?
A. Tegmentum
B. Pons
C. Cerebellum
D. Medulla oblongata

A

A. Tegmentum

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39
Q

These cells transport substances from the CSF to the hypophyseal portal system:
A. Glial cells
B. Scavenger cells
C. Tanycytes
D. Oligodendrocytes

A

C. Tanycytes

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40
Q

These cells accomplish myelination of the Peripheral Nervous System:
A. Astrocytes
B. Oligodendrocytes
C. Schwann cells
D. Radial glial cells

A

C. Schwann cells

41
Q

Which becomes the ventral horns of the spinal cord?
A. Floor plates
B. Alar plates
C. Roof plate
D. Basal plate

A

D. Basal plate

42
Q

Which of the following gives rise to the connective tissue investments of the
peripheral nerve fibers?
A. Mesoderm
B. Endoderm
C. Neural crest cells
D. Neural tube

A

A. Mesoderm

43
Q

This defect is the rarest among the vertebral arch defects?
A. Myelomeningocele
B. Myelocele
C. Syringomyelocele
D. Spina bifida occulta

A

C. Syringomyelocele

44
Q

What is the effect of caffeine on synaptic transmissions?
A. Increased excitability of Neurons
B. Decreased synaptic transmission
C. Increased neuronal excitability due to reduced threshold for excitation of neurons
D. Increased neuronal excitability by inhibition of some normally inhibitory
transmitter substances

A

C. Increased neuronal excitability due to reduced threshold for excitation of neurons

45
Q

Which is a single process that carries the output signals leaving the neuron?
A. Dendrites
B. Axon
C. Synapses
D. Soma

A

B. Axon

46
Q

To which major level of the Central Nervous System function does subconscious
control of arterial pressure and respiration belong to?
A. Spinal Cord level
B. Subcortical level
C. Cortical level
D. Higher Brain level

A

B. Subcortical level

47
Q

In which type of synapse is synaptic delay virtually absent?
A. Electrical
B. Chemical
C. Enzymatical
D. Mechanical

A

A. Electrical

48
Q

How much excitatory postsynaptic potential is required to elicit an action potential at
the axon hillock?
A. 5 mV
B. 15 mV
C. 25 mV
D. 30 mV

A

B. 15 mV

49
Q

What is the potassium diffusion potential?
A. ratio between K inside to K outside = 35: 1
B. ratio between K inside to K outside = 35: 10
C. ratio between K inside to K outside = 65: 1
D. ratio between K inside to K outside = 65: 10

A

A. ratio between K inside to K outside = 35: 1

50
Q

Which of the following tracts carry information on pain and temperature sensations?
A. Corticospinal tract
B. Spinothalamic tract
C. Dorsal column tract
D. Vestibulospinal tract

A

B. Spinothalamic tract

51
Q

The lateral corticospinal tract is associated with which type of motor function?
A. Reflexive movement
B. Skilled, voluntary movement
C. Balance and posture
D. Involuntary control

A

B. Skilled, voluntary movement

52
Q

A patient experiences loss of fine touch and proprioception in the right leg after a
spinal injury. Which of the following tracts is most likely to be affected?
A. Right dorsal column
B. Left dorsal column
C. Right corticospinal tract
D. Left spinothalamic tract

A

A. Right dorsal column

53
Q

A patient has a spinal cord injury affecting only the dorsal columns. Which of the
following would be the primary deficit?
A. Loss of pain sensation
B. Loss of proprioceptive and fine touch sensation
C. Loss of motor control
D. Loss of temperature sensation

A

B. Loss of proprioceptive and fine touch sensation

54
Q

Which tract would be most involved in coordinating postural adjustments in response
to sudden changes in head position?
A. Tectospinal tract
B. Vestibulospinal tract
C. Spinothalamic tract
D. Rubrospinal tract

A

B. Vestibulospinal tract

55
Q

Atropine blocks the effects of acetylcholine by:
A. Blocking its release from storage sites
B. Competing at receptor sites
C. Enhancing the effects of acetylcholinesterase
D. Inhibiting its synthesis

A

B. Competing at receptor sites

56
Q

Which of the choices is an antagonist to the receptor that brings about increased
heart rate when stimulated?
A. Propranolol
B. Yohimbine
C. Atropine
D. Dobutamine

A

A. Propranolol

57
Q

Which is an effect of beta-2 receptor stimulation?
A. Ejaculation
B. Bladder relaxation
C. Pupillary dilatation
D. Renin secretion

A

B. Bladder relaxation

58
Q

A patient is getting ready for an eye exam in an ophthalmology clinic. While in the waiting room, the clinic assistant administers eye drops into both of his eyes. The
patient asks what they are for and the assistant replies that they “open the eyes
more so the doctor can see inside your eyes better.” The eyedrops were which type
of drug?
A. Beta receptor blocker
B. Sympathomimetic drug
C. Antimuscarinic drug
D. Nicotinic drug

A

C. Antimuscarinic drug

59
Q

Cholinergic receptors that function by the opening of sodium-potassium channels
are found in the:
A. Central nervous system
B. Heart
C. Sweat glands
D. Autonomic ganglia

A

D. Autonomic ganglia

60
Q

Which of the following correctly identifies the sequence of components in a reflex
arc?
A. Sensory neuron → Interneuron → Motor neuron → Effector
B. Effector → Sensory neuron → Interneuron → Motor neuron
C. Sensory neuron → Effector → Motor neuron → Interneuron
D. Interneuron → Sensory neuron → Effector → Motor neuron

A

A. Sensory neuron → Interneuron → Motor neuron → Effector

61
Q

In a knee-jerk reflex, which component of the reflex arc is primarily responsible for
transmitting the signal from the muscle spindle to the spinal cord?
A. Motor neuron
B. Interneuron
C. Sensory neuron
D. Effector

A

C. Sensory neuron

62
Q

In a situation where a person touches a hot surface and quickly withdraws the hand,
which type of reflex is primarily involved?
A. Monosynaptic reflex
B. Polysynaptic reflex
C. Conditioned reflex
D. Stretch reflex

A

B. Polysynaptic reflex

63
Q

Which of the following scenarios illustrates a monosynaptic reflex?
A. The withdrawal of a hand from a painful stimulus
B. The knee-jerk reaction when the patellar tendon is tapped
C. The reflexive blinking of the eye in response to a bright light
D. The flexion of the arm when touching something hot

A

B. The knee-jerk reaction when the patellar tendon is tapped

64
Q

After an injury, a patient has impaired vibration sense in the left foot. Which tract
and side of the spinal cord is likely damaged?
A. Left dorsal column
B. Right spinothalamic tract
C. Left spinocerebellar tract
D. Right dorsal column

A

A. Left dorsal column

65
Q

What is the primary function of the spinotectal tract in the spinal cord?
A. Transmitting fine touch and proprioception
B. Coordinating reflexive movements of the head and eyes in response to visual
and auditory stimuli
C. Controlling voluntary motor movement
D. Relaying pain and temperature information

A

B. Coordinating reflexive movements of the head and eyes in response to visual
and auditory stimuli

66
Q

A patient has selective damage to the third-order neurons associated with the
spinothalamic tract. Where are these neurons located, and what type of sensory
deficits would result from this injury?
A. Located in the spinal cord, causing contralateral pain and temperature deficits
B. Located in the thalamus, causing contralateral pain and temperature deficits
C. Located in the medulla, causing ipsilateral fine touch deficits
D. Located in the cortex, causing ipsilateral proprioception deficits

A

B. Located in the thalamus, causing contralateral pain and temperature deficits

67
Q

Which pathway and structure would be most likely impacted by a lesion in the right
medial lemniscus at the level of the pons?
A. Spinothalamic tract; results in contralateral loss of pain sensation
B. Medial lemniscus; results in contralateral loss of proprioception and fine touch
C. Dorsal Column tract; results in contralateral loss of sexual sensation
D. Corticospinal tract; results in ipsilateral motor weakness

A

B. Medial lemniscus; results in contralateral loss of proprioception and fine touch

68
Q

A young adult experiences loss of pain and temperature sensation on the right side
of the body. The MRI shows a lesion in the spinal cord on the left side at the T10
level. Which sensory tract is likely affected, and where did the decussation occur?
A. Dorsal column; decussated in the medulla
B. Spinothalamic tract; decussated in the spinal cord near the level of entry
C. Corticospinal tract; decussated at the medullary pyramids
D. Vestibulospinal tract; decussated at the level of the midbrain

A

B. Spinothalamic tract; decussated in the spinal cord near the level of entry

69
Q

The internal capsule is crucial in neural communication because it:
A. Facilitates the direct connection between spinal nerves and peripheral nerves
B. Contains major ascending and descending pathways between the cerebral
cortex and lower centers
C. Is the site of integration between sensory and motor fibers in the brainstem
D. Primarily manages only sensory input from the cranial nerves

A

B. Contains major ascending and descending pathways between the cerebral
cortex and lower centers

70
Q

Which nerve cell group in the posterior gray columns is involved in processing pain
and temperature sensations?
A. Nucleus Proprius
B. Substantia Gelatinosa
C. Nucleus Dorsalis (Clarke’s Column)
D. Visceral Afferent Nucleus

A

B. Substantia Gelatinosa

71
Q

Which nerve fiber tract in the lateral funiculus transmits proprioceptive information to
the cerebellum for coordination?
A. Anterior Spinothalamic Tract
B. Vestibulospinal Tract
C. Posterior Spinocerebellar Tract
D. Reticulospinal Tract

A

C. Posterior Spinocerebellar Tract

72
Q

Which nerve fiber tract in the dorsal (posterior) funiculus carries sensory information
from the lower body?
A. Fasciculus cuneatus
B. Lateral corticospinal tract
C. Fasciculus gracilis
D. Spinothalamic tract

A

C. Fasciculus gracilis

73
Q

Which neurons are located in the lateral gray column and are involved in the
sympathetic division of the autonomic nervous system?
A. Preganglionic Parasympathetic Neurons
B. Sensory Neurons
C. Interneurons
D. Preganglionic Sympathetic Neurons

A

D. Preganglionic Sympathetic Neurons

74
Q

Which of the following is a function of the somatic nervous system?
A. Regulating heart rate
B. Digesting food
C. Voluntary muscle movement
D. Controlling hormone release

A

C. Voluntary muscle movement

75
Q

What effect does the parasympathetic nervous system have on the digestive
system?
A. Inhibits digestion
B. No effect on digestion
C. Stimulates digestion
D. Slows down digestion

A

C. Stimulates digestion

76
Q

The parasympathetic division of the ANS is also known as the:
A. Thoracolumbar
B. Craniosacral
C. Lumbar
D. Sacral

A

B. Craniosacral

77
Q

The sympathetic nervous system of the autonomic nervous system is primarily
responsible for which of the following?
A. Decreasing blood pressure
B. Increasing digestive activity
C. Promoting “fight or flight” responses
D. Slowing heart rate

A

C. Promoting “fight or flight” responses

78
Q

Paulo a 56-year-old with hypertension felt dizziness and a headache. His blood
pressure is 160/100 mmHg. Which of the following receptors detected his blood
pressure?
A. Baroreceptors
B. Krausse end bulbs
C. Osmoreceptors
D. Pacinian corpuscles

A

A. Baroreceptors

79
Q

The particular form of energy the receptor is most sensitive to.
A. Action potential
B. Subliminal stimulus
C. Facilitated stimulus
D. Adequate stimulus

A

D. Adequate stimulus

80
Q

In a blindfolded person, the minimum distance that can detect two separate points
on its fingertips is
A. 1-2mm
B. 10-15mm
C. 30-70mm
D. 200-500mm

A

A. 1-2mm

81
Q

Which principle will demonstrate the preference of a receptor to a specific type of
modality for which it is designed?
A. Amplifying divergence
B. Differential sensitivities
C. Labeled-line
D. Specific nerve energies

A

B. Differential sensitivities

82
Q

CA 35-year-old alcoholic patient has been experiencing sharp pain in the right upper
portion of the abdomen. He also felt numb pain over his right back and right scapular
region. Laboratory revealed gallbladder stones. Which statement BEST describes
the fiber(s) eliciting pain in the right back and scapular region?
A. Visceral pain fibers enter the spinal cord via the dorsal root ganglion.
B. Parietal pain fibers innervating the organ enters directly the spinal cord.
C. Visceral and skin pain fibers synapse with the same 2nd-order neuron.
D. Skin nerve fibers follow a dermatomal pattern derived from embryonic origin.

A

C. Visceral and skin pain fibers synapse with the same 2nd-order neuron.

83
Q

Which type of fiber was transmitting the pain over the right upper portion of the
abdomen?
A. Type Ia
B. Type II
C. Type III
D. Type IV

A

C. Type III

84
Q

If the receptor can adapt, which of the statements will explain its mechanism?
A. The chloride ions are abundant intracellularly.
B. The fiber did not reach threshold potential.
C. The sodium channels are still inactivated.
D. The potassium ions keep leaking out of the cell

A

C. The sodium channels are still inactivated.

85
Q

The axons of neurons whose cell bodies are located in the intermediolateral horn of
the thoracic spinal cord secrete __________.
A. acetylcholine
B. norepinephrine
C. muscarine
D. nicotine

A

A. acetylcholine

86
Q

The cell body of the postganglionic neuron of the parasympathetic nervous system
is found in the
A. organ supplied by the parasympathetic nervous system
B. intermediolateral horn of the spinal cord
C. paravertebral chain of ganglia
D. vagal nucleus of the medulla

A

A. organ supplied by the parasympathetic nervous system

87
Q

The axons of preganglionic neurons of the parasympathetic system use this
neurotransmitter.
A. acetylcholine
B. norepinephrine
C. muscarine
D. nicotine

A

A. acetylcholine

88
Q

A 20-year-old male patient has asthma. He is nebulized with Salbutamol. Which of
the following is an effect of salbutamol?
A. decreased heart rate
B. decreased force of heart muscle contraction
C. bronchodilation
D. decreased pupil size

A

C. bronchodilation

89
Q

75% of all parasympathetic fibers leave the central nervous system through which of
the following nerves?
A. olfactory nerve
B. vagus nerve
C. spinal accessory nerve
D. hypoglossal nerve

A

B. vagus nerve

90
Q

Which component of the autonomic nervous system has extremely short
postganglionic neurons?
A. sympathetic nervous system
B. parasympathetic nervous system
C. thoracolumbar autonomic nervous system
D. adrenergic nervous system

A

B. parasympathetic nervous system

91
Q

Which of the following neurotransmitters is secreted by the adrenal medulla into the
bloodstream?
A. acetylcholine
B. epinephrine
C. muscarine
D. reserpine

A

B. epinephrine

92
Q

Which step is needed for the conversion of tyrosine into norepinephrine?
A. Methylation
B. Hydroxylation and decarboxylation
C. Phosphorylation and trophotropism
D. Oxidation then decarboxylation

A

B. Hydroxylation and decarboxylation

93
Q

Which of the following enzymes is found in adrenergic nerve endings that breaks
down norepinephrine?
A. Acetylcholinesterase
B. Catechol-O-Methyltransferase
C. Monoamine oxidase
D. Choline transferase

A

C. Monoamine oxidase

94
Q

When acetylcholine undergoes degradation, what will be the products formed after
this process?
A. Acetate and Tyrosine
B. Acetate and Choline
C. Dopamine and Tyrosine
D. Choline and Tyrosine

A

B. Acetate and Choline

95
Q

Adenylyl cyclase increases the production of which second messenger?
A. cAMP
B. ATP
C. Calcium
D. Acetlyoxidase

A

A. cAMP

96
Q

Where does the spinal cord begin and terminate in adults?
A. Foramen magnum to lower border of the first lumbar vertebra
B. Medulla oblongata to sacrum
C. Upper border of the third lumbar vertebra to coccyx
D. Brainstem to the cervical region

A

A. Foramen magnum to lower border of the first lumbar vertebra

97
Q

How many pairs of spinal nerves are attached to the spinal cord?
A. 31
B. 12
C. 24
D. 8

A

A. 31

98
Q

What is the significance of the cervical and lumbar enlargements in the spinal cord?
A. They are regions of increased blood flow.
B. They provide a site for nerve roots associated with specific plexuses.
C. They are areas where the spinal cord tapers.
D. They contain additional protective layers.

A

B. They provide a site for nerve roots associated with specific plexuses.

99
Q

If a patient has an injury at the level of the third lumbar vertebra, which spinal cord
regions and nerve roots might be affected?
A. Thoracic region and upper cervical nerves
B. Lumbar region and lumbosacral plexus
C. Sacral region and coccygeal nerves
D. Cervical region and thoracic nerves

A

B. Lumbar region and lumbosacral plexus