Histology NBME Practice Exam
Questions And Answers
A 42-year-old man comes to the physician because of multiple
lesions over his body. Physical examination shows flaccid bullous
erosions involving the upper and lower extremities. A biopsy
specimen of one of the lesions shows extensive epidermal
acantholysis resulting in the formation of an intraepidermal blister.
An intact basal layer of keratinocytes adherent to the basement
membrane is identified. Which of the following is most likely
related to the pathogenesis of this disorder?
Select one:
a. Immediate (type I) hypersensitivity reaction to a topically applied
agent
b. Infection with a herpesvirus
c. Development of autoantibodies against desmosomal proteins
d. Deposition of lgA-containing immune complexes within dermal
papilla
e. Mutation of an anchoring filament protein - - correct answer
✅c. Development of autoantibodies against desmosomal proteins
A 75 year old man presents to the orthopedic clinic with the
complaint of bone pain. His laboratory report shows elevated level
of serum alkaline phosphatase. A histologic examination shows
haphazardly oriented, prominent cement lines, that create a mosaic
,Histology NBME Practice Exam
Questions And Answers
pattern of lamellar bone. Which of the following cell types is most
likely involved in the initial lesion of his condition?
Select one:
a. Osteoclasts
b. Osteoblasts
c. Fibroblast
d. Endothelial cells
e. Chondrocytes - - correct answer ✅a. Osteoclasts
A 50-year-old woman is brought to the emergency department
because of a 2-hour history of shortness of breath and chest pain
that radiates to her back between the shoulder blades. Her
respirations are 28/min. Physical examination shows diaphoresis.
An ECG shows no abnormalities. Coronary angiography shows
occlusion of the marginal branch of the left anterior descending
coronary artery. A percutaneous coronary revascularization is done.
Due to revascularization free radicals mediate cardiac muscles
injury expected because her serum concentrations of myocardial
creatine kinase (CK-MB) and troponin I are increased. Which of the
following mechanisms best explains these laboratory findings?
Select one:
a. Membrane lipid peroxidation
b. Liquefactive necrosis of the myocardium
,Histology NBME Practice Exam
Questions And Answers
c. Cell shrinkage
d. Protease inactivation by cytoplasmic free calcium ions
e. Formation of apoptotic bodies - - correct answer ✅a.
Membrane lipid peroxidation
Which of the following cells in the inner ear are involved in
detecting movements of the head?
Select one:
a. Outer pillar cells
b. Cells of Hensen
c. Inner pillar cells
d. Hair cells in the organ of Corti
e. Hair cells in the maculae - - correct answer ✅e. Hair cells in the
maculae
An 11-year-old boy has repeated episodes of staphylococcal
pneumonia. When incubated in vitro with Staphylococcus aureus,
his peripheral blood neutrophils fail to demonstrate a respiratory
burst and do not kill the microorganisms, even though electron
microscopy of the neutrophils shows bacterial cells within
, Histology NBME Practice Exam
Questions And Answers
phagosomes. This failure to kill phagocytosed organisms is due to a
deficiency of which of the following?
Select one:
a. Lactoferrin
b. NADPH oxidase
c. Superoxide dismutase
d. Lysozyme
e. Lysosomal proteases - - correct answer ✅b. NADPH oxidase
A 76-year-old man with congestive heart failure comes to the
physician because of a 1-month history of shortness of breath after
walking up a flight of stairs. He has had frequent nausea, and he
has had to use two pillows to sleep during this period. Diffuse,
moist crackles are heard over both lungs. There is pitting edema
above the ankles. Which of the following best describes the
function of the product secreted by the atrial myocytes in this
patient?
Select one:
a. Decreased glomerular filtration rate
b. Increased sodium reabsorption
c. Induction of vasoconstriction
Questions And Answers
A 42-year-old man comes to the physician because of multiple
lesions over his body. Physical examination shows flaccid bullous
erosions involving the upper and lower extremities. A biopsy
specimen of one of the lesions shows extensive epidermal
acantholysis resulting in the formation of an intraepidermal blister.
An intact basal layer of keratinocytes adherent to the basement
membrane is identified. Which of the following is most likely
related to the pathogenesis of this disorder?
Select one:
a. Immediate (type I) hypersensitivity reaction to a topically applied
agent
b. Infection with a herpesvirus
c. Development of autoantibodies against desmosomal proteins
d. Deposition of lgA-containing immune complexes within dermal
papilla
e. Mutation of an anchoring filament protein - - correct answer
✅c. Development of autoantibodies against desmosomal proteins
A 75 year old man presents to the orthopedic clinic with the
complaint of bone pain. His laboratory report shows elevated level
of serum alkaline phosphatase. A histologic examination shows
haphazardly oriented, prominent cement lines, that create a mosaic
,Histology NBME Practice Exam
Questions And Answers
pattern of lamellar bone. Which of the following cell types is most
likely involved in the initial lesion of his condition?
Select one:
a. Osteoclasts
b. Osteoblasts
c. Fibroblast
d. Endothelial cells
e. Chondrocytes - - correct answer ✅a. Osteoclasts
A 50-year-old woman is brought to the emergency department
because of a 2-hour history of shortness of breath and chest pain
that radiates to her back between the shoulder blades. Her
respirations are 28/min. Physical examination shows diaphoresis.
An ECG shows no abnormalities. Coronary angiography shows
occlusion of the marginal branch of the left anterior descending
coronary artery. A percutaneous coronary revascularization is done.
Due to revascularization free radicals mediate cardiac muscles
injury expected because her serum concentrations of myocardial
creatine kinase (CK-MB) and troponin I are increased. Which of the
following mechanisms best explains these laboratory findings?
Select one:
a. Membrane lipid peroxidation
b. Liquefactive necrosis of the myocardium
,Histology NBME Practice Exam
Questions And Answers
c. Cell shrinkage
d. Protease inactivation by cytoplasmic free calcium ions
e. Formation of apoptotic bodies - - correct answer ✅a.
Membrane lipid peroxidation
Which of the following cells in the inner ear are involved in
detecting movements of the head?
Select one:
a. Outer pillar cells
b. Cells of Hensen
c. Inner pillar cells
d. Hair cells in the organ of Corti
e. Hair cells in the maculae - - correct answer ✅e. Hair cells in the
maculae
An 11-year-old boy has repeated episodes of staphylococcal
pneumonia. When incubated in vitro with Staphylococcus aureus,
his peripheral blood neutrophils fail to demonstrate a respiratory
burst and do not kill the microorganisms, even though electron
microscopy of the neutrophils shows bacterial cells within
, Histology NBME Practice Exam
Questions And Answers
phagosomes. This failure to kill phagocytosed organisms is due to a
deficiency of which of the following?
Select one:
a. Lactoferrin
b. NADPH oxidase
c. Superoxide dismutase
d. Lysozyme
e. Lysosomal proteases - - correct answer ✅b. NADPH oxidase
A 76-year-old man with congestive heart failure comes to the
physician because of a 1-month history of shortness of breath after
walking up a flight of stairs. He has had frequent nausea, and he
has had to use two pillows to sleep during this period. Diffuse,
moist crackles are heard over both lungs. There is pitting edema
above the ankles. Which of the following best describes the
function of the product secreted by the atrial myocytes in this
patient?
Select one:
a. Decreased glomerular filtration rate
b. Increased sodium reabsorption
c. Induction of vasoconstriction
