Digestive System Questions and Answers

Answer: A

The portal triad consists of the hepatic artery, portal vein and bile duct.

At each corner of a classic hepatic lobule lies a portal tract holding a branch of the hepatic artery, a branch of the hepatic portal vein and a bile ductule. Blood from the artery and portal vein flows through the sinusoids towards the central vein, while bile flows the other way, towards the duct.

Hepatic veins (and the central veins that drain into them) carry blood out of the liver and are not in the triad. The inferior vena cava is outside the lobule altogether. Lymphatics run in the portal tract but are not one of the three classic structures.

Answer: C

The chief cells secrete pepsinogen.

Chief (peptic, zymogenic) cells at the base of the gastric glands release pepsinogen, the inactive precursor of pepsin, together with gastric lipase. Acid in the lumen converts pepsinogen to pepsin, which then activates more pepsinogen.

Hydrochloric acid and intrinsic factor are both secreted by the parietal (oxyntic) cells. Gastrin is a hormone released by the G cells of the antrum.