Advanced Ileum Quiz

Q1. Which combination best distinguishes ileum from jejunum during gross examination?

• Fewer arcades, longer vasa recta, less mesenteric fat, and larger folds
• No mesentery, no arcades, and no villi
• Taeniae coli, haustra, and appendices epiploicae
• More arcades, shorter vasa recta, more mesenteric fat, and less prominent plicae circulares

Q2. Why are the arterial arcades of the ileum anatomically important?

• They form interconnected arterial pathways that give rise to vasa recta
• They form the lymphatic lacteals
• They drain venous blood into the inferior vena cava
• They attach the ileum to the liver

Q3. How does the root of the small intestinal mesentery relate to posterior abdominal structures?

• It runs horizontally along the diaphragm
• It attaches only to the anterior abdominal wall
• It crosses multiple retroperitoneal structures as it runs obliquely toward the right iliac fossa
• It lies entirely within the pelvis

Q4. Why is the terminal ileum closely related to cecal and appendiceal vascular anatomy?

• They are supplied only by the celiac trunk
• The ileocolic artery supplies the terminal ileum and adjacent ileocecal structures
• The left colic artery supplies all three structures
• They have no shared arterial territory

Q5. Which statement best describes sympathetic innervation of the ileum?

• The vagus nerve carries sympathetic fibers to it
• Postganglionic sympathetic fibers reach it through the superior mesenteric periarterial plexus
• Pelvic splanchnic nerves provide its sympathetic supply
• The pudendal nerve supplies its smooth muscle

Q6. Why is visceral pain from the ileum commonly referred toward the periumbilical region?

• Midgut visceral afferents commonly project to spinal levels associated with the periumbilical region
• The ileum has only somatic sensory innervation
• The ileum is innervated by the phrenic nerve
• Its afferents enter only sacral spinal levels

Q7. How does ileal lymphatic anatomy support absorption of dietary lipids?

• Peyer patches secrete bile into the lumen
• Lacteals in villi drain absorbed lipids into mesenteric lymphatics
• Arterial arcades transport dietary fat
• Portal venules directly absorb all chylomicrons

Q8. Which embryologic event explains why the ileum and cecum occupy related right lower abdominal positions?

• Fusion of the dorsal pancreatic bud
• Hindgut descent through the diaphragm
• Foregut rotation around the celiac trunk
• Midgut rotation and return establish their adult relationships

Q9. Why can a Meckel diverticulum be found on the ileum?

• It is formed by persistence of the urachus
• It is an acquired diverticulum of the mesenteric border only
• It results from persistence of the vitelline duct and usually arises from the antimesenteric ileal border
• It develops from the dorsal pancreatic duct

Q10. Which statement best integrates the anatomy of the ileum?

• It is a foregut organ suspended by the lesser omentum
• It is an extraperitoneal pelvic organ without autonomic innervation
• It is an intraperitoneal midgut segment with mesenteric, superior mesenteric vascular, lymphatic, and vagal relationships
• It is a fixed retroperitoneal hindgut segment supplied by the inferior mesenteric artery