Saturn Medic
Embryology (Digestive System)
MCQ
1 / 13
A 2-month-old baby with severe jaundice also has dark-colored urine (deep yellow) and white clay-colored stool. Which of the following disorders might be suspected?
The baby is suffering from extrahepatic biliary atresia, which results from failure of the bile ducts to recanalize during development. This prevents bile from entering the duodenum
2 / 13
A 4-day-old baby boy has not defecated since coming home from the hospital even though feeding has been normal without any excessive vomiting. Rectal examination reveals a normal anus, anal canal, and rectum. However, a large fecal mass is found in the colon, and a large release of flatus and feces follows the rectal examination. Which of the following conditions would be suspected?
This baby boy suffers from colonic aganglionosis, or Hirschsprung disease, which results in the retention of fecal material, causing the normal colon to enlarge. The retention of fecal material results from a lack of peristalsis in the narrow segment of colon distal to the enlarged colon. A biopsy of the narrow segment of colon would reveal the absence of parasympathetic ganglion cells in the myenteric plexus caused by failure of neural crest migration
3 / 13
The midgut loop normally herniates through the primitive umbilical ring into the extraembryonic coelom during week 6 of development. Failure of the intestinal loops to return to the abdominal cavity by week 11 results in the formation of
An omphalocele results when intestinal loops fail to return to the abdominal cavity. Instead, the intestinal loops remain in the umbilical cord covered by amnion.
4 / 13
A 28-day-old baby is brought to the physician because of projectile vomiting after feeding. Until this time, the baby has had no problems in feeding. On examination, a small knot is palpated at the right costal margin. Which of the following disorders might be suspected?
The baby is suffering from hypertrophic pyloric stenosis. This occurs when the smooth muscle in the pyloric region of the stomach hypertrophies and obstructs passage of food. The hypertrophied muscle can be palpated at the right costal margin. The exact cause of this condition is not known.
5 / 13
The simple columnar or cuboidal epithelium lining the extrahepatic biliary ducts is derived from
The epithelium lining the extrahepatic biliary ducts is derived from endoderm. The intrahepatic biliary ducts are also derived from endoderm.
6 / 13
The simple columnar and stratified columnar epithelia lining the lower part of the anal canal is derived from
The anal canal is formed from two components—the hindgut and proctodeum. The epithelium lining the lower anal canal is derived from ectoderm lining the proctodeum.
7 / 13
The most common type of anorectal malformation is
The most common type of malformation involving the anal canal and rectum is anorectal agenesis, in which the rectum ends as a blind sac above the puborectalis muscle. The anal canal may form normally but does not connect with the rectum. This malformation is accompanied by various fistulas.
8 / 13
Kupffer cells present in the adult liver are derived from
Kupffer cells are actually macrophages and are derived from mesoderm. Hepatocytes and the epithelial lining of the intrahepatic biliary tree are derived from endoderm.
9 / 13
A baby born to a young woman whose pregnancy was complicated by polyhydramnios was placed in the intensive care unit because of repeated vomiting containing bile. The stomach was markedly distended, and only small amounts of meconium had passed through the anus. What is the most likely diagnosis?
This baby is suffering from duodenal atresia at a level distal to the opening of the common bile duct. This causes a reflux of bile and its presence in the vomitus. The pregnancy was complicated by polyhydramnios because the duodenal atresia prevented passage of amniotic fluid into the intestines for absorption.
10 / 13
Which of the following arteries supplies foregut derivatives of the digestive system?
The artery that supplies foregut derivatives of the digestive system is the celiac trunk. The celiac trunk consists of the left gastric artery, splenic artery, and common hepatic artery. The superior mesenteric artery supplies the midgut, and the inferior mesenteric artery supplies the hindgut.
11 / 13
Pancreatic islets consist of alpha, beta, and delta cells, which secrete glucagon, insulin, and somatostatin, respectively. These cells are derived from
Pancreatic islets form as isolated clumps of cells that bud from endodermal tubules.
12 / 13
Which one of the following structures is derived from the midgut?
The appendix is derived from the midgut. The midgut normally undergoes a 270° counterclockwise rotation during development; malrotation of the midgut may result in the appendix lying in the upper part of the abdominal cavity, which may affect a diagnosis of appendicitis.
13 / 13
A 3-month-old baby girl presents with a swollen umbilicus that has failed to heal normally. The umbilicus drains secretions, and there is passage of fecal material through the umbilicus at times. What is the most likely diagnosis?
This baby girl has an ileal diverticulum (Meckel diverticulum), which occurs when a remnant of the vitelline duct persists. In this case, a fistula is present by which contents of the ileum can be discharged onto the surface of the skin.
Your score is
The average score is 0%
Restart quiz
