Stanford University MD SURG 203 Anatomy
(Macroscopic, Embryology and Histology) –
Stanford Medical School Anatomy Study Guide,
Original Practice Questions & Answers, SURG 203
Exam Preparation, Comprehensive Clinical
Anatomy Review, Gross Anatomy, Macroscopic
Anatomy, Embryology, Histology, Developmental
Anatomy, Medical Imaging, Dissection, Thorax,
Abdomen, Pelvis, Back, Upper & Lower Limbs, Head
& Neck & Clinical Applications
Question 1: Which of the following best describes the anatomical position of
the kidneys relative to the peritoneal cavity?
A. Intraperitoneal organs suspended by the mesentery
B. Retroperitoneal organs located posterior to the parietal peritoneum
C. Infraperitoneal organs situated within the pelvic cavity
D. Supraperitoneal organs embedded in the diaphragm
CORRECT ANSWER: B. Retroperitoneal organs located posterior to the parietal
peritoneum
Rationale: The kidneys are retroperitoneal organs, meaning they lie behind the parietal
peritoneum on the posterior abdominal wall. They are not intraperitoneal like the
stomach or liver, nor are they infraperitoneal or supraperitoneal.
Question 2: During the fourth week of development, the lateral mesoderm
splits into which two layers?
A. Ectoderm and endoderm
B. Somatic and splanchnic mesoderm
C. Paraxial and intermediate mesoderm
D. Epimere and hypomere
CORRECT ANSWER: B. Somatic and splanchnic mesoderm
Rationale: The lateral plate mesoderm splits into the somatic (parietal) layer, which lines
the body wall, and the splanchnic (visceral) layer, which surrounds the developing gut.
Paraxial mesoderm forms somites, and intermediate mesoderm forms the urogenital
system.
Question 3: Which histological feature is characteristic of the transitional
epithelium lining the urinary bladder?
,A. Pseudostratified columnar cells with cilia
B. Stratified squamous cells with keratinization
C. Superficial umbrella cells that are dome-shaped and multinucleated
D. Simple cuboidal cells with a brush border
CORRECT ANSWER: C. Superficial umbrella cells that are dome-shaped and
multinucleated
Rationale: Transitional epithelium (urothelium) is unique to the urinary tract. Its
superficial layer consists of large, dome-shaped umbrella cells that can change shape to
accommodate distension. It is neither squamous, columnar, nor ciliated.
Question 4: The portal triad in the liver lobule contains which of the following
three structures?
A. Central vein, hepatic sinusoids, and bile canaliculi
B. Portal vein, hepatic artery, and bile duct
C. Hepatic vein, portal vein, and lymphatic vessel
D. Kupffer cells, stellate cells, and hepatocytes
CORRECT ANSWER: B. Portal vein, hepatic artery, and bile duct
Rationale: The portal triad (portal tract) is a component of the classical liver lobule and
contains a branch of the portal vein, a branch of the hepatic artery, and an interlobular
bile duct. The central vein is in the center of the lobule, not the triad.
Question 5: In the embryo, the notochord is derived from which germ layer
and induces the formation of which structure?
A. Ectoderm; neural tube
B. Mesoderm; neural crest cells
C. Endoderm; somites
D. Mesoderm; neural tube
CORRECT ANSWER: D. Mesoderm; neural tube
Rationale: The notochord is derived from the axial mesoderm. It secretes signaling
molecules, such as Sonic Hedgehog (Shh), that induce the overlying ectoderm to thicken
and form the neural plate, which folds into the neural tube.
Question 6: Which muscle of the thenar eminence is innervated by the ulnar
nerve?
A. Abductor pollicis brevis
B. Flexor pollicis brevis (superficial head)
,C. Opponens pollicis
D. Adductor pollicis
CORRECT ANSWER: D. Adductor pollicis
Rationale: The adductor pollicis is the only muscle of the thenar eminence innervated by
the ulnar nerve (deep branch). The other thenar muscles are innervated by the median
nerve (recurrent branch). The deep head of flexor pollicis brevis may sometimes have
dual innervation, but the adductor is purely ulnar.
Question 7: Which congenital anomaly results from the failure of the urethral
folds to fuse completely in the male fetus?
A. Epispadias
B. Hypospadias
C. Bladder exstrophy
D. Urachal fistula
CORRECT ANSWER: B. Hypospadias
Rationale: Hypospadias is the most common congenital anomaly of the penis, where the
urethral meatus opens on the ventral side due to incomplete fusion of the urethral folds.
Epispadias is dorsal and associated with bladder exstrophy, which is a more severe
midline defect.
Question 8: In histological sections, which cell type is responsible for the
secretion of hydrochloric acid in the stomach?
A. Chief cells
B. Parietal cells
C. Mucous neck cells
D. Enteroendocrine cells
CORRECT ANSWER: B. Parietal cells
Rationale: Parietal (oxyntic) cells are located in the gastric glands and secrete
hydrochloric acid and intrinsic factor. Chief cells secrete pepsinogen, mucous neck cells
produce mucus, and enteroendocrine cells secrete various hormones.
Question 9: The superior orbital fissure transmits all of the following EXCEPT:
A. Oculomotor nerve (CN III)
B. Trochlear nerve (CN IV)
C. Optic nerve (CN II)
D. Abducens nerve (CN VI)
, CORRECT ANSWER: C. Optic nerve (CN II)
Rationale: The optic nerve (CN II) passes through the optic canal, not the superior
orbital fissure. The superior orbital fissure transmits CN III, IV, V1 (ophthalmic division),
VI, and the superior and inferior ophthalmic veins.
Question 10: During development, the metanephric duct gives rise to which of
the following adult structures?
A. Ureter, renal pelvis, calyces, and collecting ducts
B. Glomerulus and Bowman's capsule
C. Proximal and distal convoluted tubules
D. Loop of Henle
CORRECT ANSWER: A. Ureter, renal pelvis, calyces, and collecting ducts
Rationale: The metanephric duct (ureteric bud) gives rise to the ureter, renal pelvis,
major and minor calyces, and collecting ducts. The nephron components (glomerulus,
Bowman's capsule, proximal/distal tubules, and Loop of Henle) are derived from the
metanephric mesenchyme.
Question 11: Which histological layer of the esophagus is unique in that it is
composed of stratified squamous epithelium that transitions to simple
columnar at the gastroesophageal junction?
A. Tunica mucosa
B. Tunica submucosa
C. Tunica muscularis
D. Tunica adventitia
CORRECT ANSWER: A. Tunica mucosa
Rationale: The mucosa of the esophagus is lined by non-keratinized stratified squamous
epithelium. At the gastroesophageal junction, this abruptly changes to the simple
columnar epithelium of the stomach. This epithelial transition is a hallmark of the
mucosa.
Question 12: The scapular anastomosis provides a collateral circulation
around the shoulder. Which artery is the primary connection between the
subclavian and axillary systems in this network?
A. Suprascapular artery
B. Circumflex scapular artery
C. Dorsal scapular artery
D. Thoracoacromial artery
(Macroscopic, Embryology and Histology) –
Stanford Medical School Anatomy Study Guide,
Original Practice Questions & Answers, SURG 203
Exam Preparation, Comprehensive Clinical
Anatomy Review, Gross Anatomy, Macroscopic
Anatomy, Embryology, Histology, Developmental
Anatomy, Medical Imaging, Dissection, Thorax,
Abdomen, Pelvis, Back, Upper & Lower Limbs, Head
& Neck & Clinical Applications
Question 1: Which of the following best describes the anatomical position of
the kidneys relative to the peritoneal cavity?
A. Intraperitoneal organs suspended by the mesentery
B. Retroperitoneal organs located posterior to the parietal peritoneum
C. Infraperitoneal organs situated within the pelvic cavity
D. Supraperitoneal organs embedded in the diaphragm
CORRECT ANSWER: B. Retroperitoneal organs located posterior to the parietal
peritoneum
Rationale: The kidneys are retroperitoneal organs, meaning they lie behind the parietal
peritoneum on the posterior abdominal wall. They are not intraperitoneal like the
stomach or liver, nor are they infraperitoneal or supraperitoneal.
Question 2: During the fourth week of development, the lateral mesoderm
splits into which two layers?
A. Ectoderm and endoderm
B. Somatic and splanchnic mesoderm
C. Paraxial and intermediate mesoderm
D. Epimere and hypomere
CORRECT ANSWER: B. Somatic and splanchnic mesoderm
Rationale: The lateral plate mesoderm splits into the somatic (parietal) layer, which lines
the body wall, and the splanchnic (visceral) layer, which surrounds the developing gut.
Paraxial mesoderm forms somites, and intermediate mesoderm forms the urogenital
system.
Question 3: Which histological feature is characteristic of the transitional
epithelium lining the urinary bladder?
,A. Pseudostratified columnar cells with cilia
B. Stratified squamous cells with keratinization
C. Superficial umbrella cells that are dome-shaped and multinucleated
D. Simple cuboidal cells with a brush border
CORRECT ANSWER: C. Superficial umbrella cells that are dome-shaped and
multinucleated
Rationale: Transitional epithelium (urothelium) is unique to the urinary tract. Its
superficial layer consists of large, dome-shaped umbrella cells that can change shape to
accommodate distension. It is neither squamous, columnar, nor ciliated.
Question 4: The portal triad in the liver lobule contains which of the following
three structures?
A. Central vein, hepatic sinusoids, and bile canaliculi
B. Portal vein, hepatic artery, and bile duct
C. Hepatic vein, portal vein, and lymphatic vessel
D. Kupffer cells, stellate cells, and hepatocytes
CORRECT ANSWER: B. Portal vein, hepatic artery, and bile duct
Rationale: The portal triad (portal tract) is a component of the classical liver lobule and
contains a branch of the portal vein, a branch of the hepatic artery, and an interlobular
bile duct. The central vein is in the center of the lobule, not the triad.
Question 5: In the embryo, the notochord is derived from which germ layer
and induces the formation of which structure?
A. Ectoderm; neural tube
B. Mesoderm; neural crest cells
C. Endoderm; somites
D. Mesoderm; neural tube
CORRECT ANSWER: D. Mesoderm; neural tube
Rationale: The notochord is derived from the axial mesoderm. It secretes signaling
molecules, such as Sonic Hedgehog (Shh), that induce the overlying ectoderm to thicken
and form the neural plate, which folds into the neural tube.
Question 6: Which muscle of the thenar eminence is innervated by the ulnar
nerve?
A. Abductor pollicis brevis
B. Flexor pollicis brevis (superficial head)
,C. Opponens pollicis
D. Adductor pollicis
CORRECT ANSWER: D. Adductor pollicis
Rationale: The adductor pollicis is the only muscle of the thenar eminence innervated by
the ulnar nerve (deep branch). The other thenar muscles are innervated by the median
nerve (recurrent branch). The deep head of flexor pollicis brevis may sometimes have
dual innervation, but the adductor is purely ulnar.
Question 7: Which congenital anomaly results from the failure of the urethral
folds to fuse completely in the male fetus?
A. Epispadias
B. Hypospadias
C. Bladder exstrophy
D. Urachal fistula
CORRECT ANSWER: B. Hypospadias
Rationale: Hypospadias is the most common congenital anomaly of the penis, where the
urethral meatus opens on the ventral side due to incomplete fusion of the urethral folds.
Epispadias is dorsal and associated with bladder exstrophy, which is a more severe
midline defect.
Question 8: In histological sections, which cell type is responsible for the
secretion of hydrochloric acid in the stomach?
A. Chief cells
B. Parietal cells
C. Mucous neck cells
D. Enteroendocrine cells
CORRECT ANSWER: B. Parietal cells
Rationale: Parietal (oxyntic) cells are located in the gastric glands and secrete
hydrochloric acid and intrinsic factor. Chief cells secrete pepsinogen, mucous neck cells
produce mucus, and enteroendocrine cells secrete various hormones.
Question 9: The superior orbital fissure transmits all of the following EXCEPT:
A. Oculomotor nerve (CN III)
B. Trochlear nerve (CN IV)
C. Optic nerve (CN II)
D. Abducens nerve (CN VI)
, CORRECT ANSWER: C. Optic nerve (CN II)
Rationale: The optic nerve (CN II) passes through the optic canal, not the superior
orbital fissure. The superior orbital fissure transmits CN III, IV, V1 (ophthalmic division),
VI, and the superior and inferior ophthalmic veins.
Question 10: During development, the metanephric duct gives rise to which of
the following adult structures?
A. Ureter, renal pelvis, calyces, and collecting ducts
B. Glomerulus and Bowman's capsule
C. Proximal and distal convoluted tubules
D. Loop of Henle
CORRECT ANSWER: A. Ureter, renal pelvis, calyces, and collecting ducts
Rationale: The metanephric duct (ureteric bud) gives rise to the ureter, renal pelvis,
major and minor calyces, and collecting ducts. The nephron components (glomerulus,
Bowman's capsule, proximal/distal tubules, and Loop of Henle) are derived from the
metanephric mesenchyme.
Question 11: Which histological layer of the esophagus is unique in that it is
composed of stratified squamous epithelium that transitions to simple
columnar at the gastroesophageal junction?
A. Tunica mucosa
B. Tunica submucosa
C. Tunica muscularis
D. Tunica adventitia
CORRECT ANSWER: A. Tunica mucosa
Rationale: The mucosa of the esophagus is lined by non-keratinized stratified squamous
epithelium. At the gastroesophageal junction, this abruptly changes to the simple
columnar epithelium of the stomach. This epithelial transition is a hallmark of the
mucosa.
Question 12: The scapular anastomosis provides a collateral circulation
around the shoulder. Which artery is the primary connection between the
subclavian and axillary systems in this network?
A. Suprascapular artery
B. Circumflex scapular artery
C. Dorsal scapular artery
D. Thoracoacromial artery
