USMLE Step 1 Qs (2) latest practice test with
best problems and solutions
1/50 Questions
The structures labeled in the figure with an
asterisk produce which of the following substances? - ProProfs
The structures labeled in the figure with an asterisk produce which of the following substances?
Acid
Mucus and HCO3–
Pepsinogen
Lysozyme
Enterokinase
Start
USMLE Step 1 Qs (2) - Quiz
About This Quiz
This USMLE Step 1 quiz assesses knowledge in various medical conditions and pathologies,
focusing on diagnosis and physiological understanding. It is designed for medical students
preparing for the USMLE Step 1 exam, enhancing their clinical reasoning and problem-solving
skills.
,Quiz Preview
2.
A 24-year-old male visited the community clinic complaining of a draining abscess on his
anterior thigh. Subsequent testing revealed an active tuberculosis infection localized in the
lumbar vertebrae. The spread of infection most likely occurred via which of the following?
The ischiorectal fossa
The sheath of the psoas muscle
The inguinal ligament
A paracolic gutter
Correct Answer
A. The sheath of the psoas muscle
Explanation
Tuberculous infections of the lumbar vertebrae are frequently communicated to the sheath of
the adjacent psoas muscles. Subsequently, pus may travel inferiorly over the pelvic brim and
erupt on the anterior thigh near the insertion of the psoas on the lesser trochanter of the
femur. Abscesses in the ischiorectal fossae may drain into the pelvis or the anal canal. The
inguinal ligament passes laterally to medially superficial to the psoas muscle to transmit
contents to the scrotum or labia. Its origin in the anterolateral abdominal wall is not in close
approximation to the lumbar vertebrae. The paracolic gutters can spread infection or
metastases into the pelvis or the subphrenic region, depending on whether the patient is erect
or supine.
,Rate this question:
3.
In hemolytic jaundice, the structure labeled
with the arrow in the accompanying photomicrograph will contain which of the
following?
- ProProfs
In hemolytic jaundice, the structure labeled with the arrow in the accompanying
photomicrograph will contain which of the following?
Elevated urobilinogen levels
Elevated bilirubin levels
Decreased urobilinogen levels
Decreased bilirubin levels
Elevated numbers of lymphocytes undergoing diapedesis
, Correct Answer
A. Elevated bilirubin levels
Explanation
The structure labeled with the arrow is a bile duct and would contain elevated levels of bilirubin
following hemolytic jaundice. Hemolytic jaundice is associated predominantly with
unconjugated hyperbilirubinemia. The overproduction of bilirubin occurs because of
accelerated intravascular erythrocyte destruction or resorption of a large hematoma. When the
hepatic uptake and/or excretion of urobilinogen is (are) impaired or the production of bilirubin
is greatly increased (e.g., with hemolysis) daily urinary urobilinogen excretion may increase
significantly. In contrast, cholestasis [arrested flow of bile due to obstruction of the bile ducts
(intrahepatic)] or extrahepatic biliary obstruction interferes with the intestinal phase of bilirubin
metabolism and leads to significantly decreased production and urinary excretion of
urobilinogen. Diapedesis of lymphocytes across the endothelium of the postcapillary high
endothelial venules of lymphoid organs (e.g., lymph nodes) increases during inflammation.
Bile is formed by the hepatocytes and is released into bile canaliculi, which are located between
the lateral surfaces of adjacent hepatocytes. The direction of flow is from the hepatocytes
toward the bile duct, which drains bile from the liver on its path to the gallbladder, where the
bile is stored and concentrated. The hepatic artery and hepatic portal vein (shown in the
photomicrograph) plus the bile duct comprise the portal triad. Blood flows from the triad
(hepatic artery, portal vein, and bile duct) toward the central vein, whereas bile flows in the
opposite direction toward the triad.
Bile is synthesized by hepatocytes using the smooth endoplasmic reticulum (SER) and consists
of bile acids and bilirubin. Bile acids are 90% reused from the distal small and large intestinal
lumen and 10% newly synthesized by conjugation of cholic acid, glycine, and taurine in the SER.
Bilirubin is the breakdown product of hemoglobin derived from the action of Kupffer cells in
hepatic sinusoids and other macrophages, particularly those lining the sinusoids of the spleen
where degradation of RBCs is prominent.
Rate this question:
4.
best problems and solutions
1/50 Questions
The structures labeled in the figure with an
asterisk produce which of the following substances? - ProProfs
The structures labeled in the figure with an asterisk produce which of the following substances?
Acid
Mucus and HCO3–
Pepsinogen
Lysozyme
Enterokinase
Start
USMLE Step 1 Qs (2) - Quiz
About This Quiz
This USMLE Step 1 quiz assesses knowledge in various medical conditions and pathologies,
focusing on diagnosis and physiological understanding. It is designed for medical students
preparing for the USMLE Step 1 exam, enhancing their clinical reasoning and problem-solving
skills.
,Quiz Preview
2.
A 24-year-old male visited the community clinic complaining of a draining abscess on his
anterior thigh. Subsequent testing revealed an active tuberculosis infection localized in the
lumbar vertebrae. The spread of infection most likely occurred via which of the following?
The ischiorectal fossa
The sheath of the psoas muscle
The inguinal ligament
A paracolic gutter
Correct Answer
A. The sheath of the psoas muscle
Explanation
Tuberculous infections of the lumbar vertebrae are frequently communicated to the sheath of
the adjacent psoas muscles. Subsequently, pus may travel inferiorly over the pelvic brim and
erupt on the anterior thigh near the insertion of the psoas on the lesser trochanter of the
femur. Abscesses in the ischiorectal fossae may drain into the pelvis or the anal canal. The
inguinal ligament passes laterally to medially superficial to the psoas muscle to transmit
contents to the scrotum or labia. Its origin in the anterolateral abdominal wall is not in close
approximation to the lumbar vertebrae. The paracolic gutters can spread infection or
metastases into the pelvis or the subphrenic region, depending on whether the patient is erect
or supine.
,Rate this question:
3.
In hemolytic jaundice, the structure labeled
with the arrow in the accompanying photomicrograph will contain which of the
following?
- ProProfs
In hemolytic jaundice, the structure labeled with the arrow in the accompanying
photomicrograph will contain which of the following?
Elevated urobilinogen levels
Elevated bilirubin levels
Decreased urobilinogen levels
Decreased bilirubin levels
Elevated numbers of lymphocytes undergoing diapedesis
, Correct Answer
A. Elevated bilirubin levels
Explanation
The structure labeled with the arrow is a bile duct and would contain elevated levels of bilirubin
following hemolytic jaundice. Hemolytic jaundice is associated predominantly with
unconjugated hyperbilirubinemia. The overproduction of bilirubin occurs because of
accelerated intravascular erythrocyte destruction or resorption of a large hematoma. When the
hepatic uptake and/or excretion of urobilinogen is (are) impaired or the production of bilirubin
is greatly increased (e.g., with hemolysis) daily urinary urobilinogen excretion may increase
significantly. In contrast, cholestasis [arrested flow of bile due to obstruction of the bile ducts
(intrahepatic)] or extrahepatic biliary obstruction interferes with the intestinal phase of bilirubin
metabolism and leads to significantly decreased production and urinary excretion of
urobilinogen. Diapedesis of lymphocytes across the endothelium of the postcapillary high
endothelial venules of lymphoid organs (e.g., lymph nodes) increases during inflammation.
Bile is formed by the hepatocytes and is released into bile canaliculi, which are located between
the lateral surfaces of adjacent hepatocytes. The direction of flow is from the hepatocytes
toward the bile duct, which drains bile from the liver on its path to the gallbladder, where the
bile is stored and concentrated. The hepatic artery and hepatic portal vein (shown in the
photomicrograph) plus the bile duct comprise the portal triad. Blood flows from the triad
(hepatic artery, portal vein, and bile duct) toward the central vein, whereas bile flows in the
opposite direction toward the triad.
Bile is synthesized by hepatocytes using the smooth endoplasmic reticulum (SER) and consists
of bile acids and bilirubin. Bile acids are 90% reused from the distal small and large intestinal
lumen and 10% newly synthesized by conjugation of cholic acid, glycine, and taurine in the SER.
Bilirubin is the breakdown product of hemoglobin derived from the action of Kupffer cells in
hepatic sinusoids and other macrophages, particularly those lining the sinusoids of the spleen
where degradation of RBCs is prominent.
Rate this question:
4.
