Final answer:
The hepatic portal vein receives blood from various organs in the digestive system and delivers it to the liver for processing. It starts at the confluence of the superior mesenteric and splenic veins and receives branches from the inferior mesenteric vein, splenic veins, gastric veins, and cystic veins. The hepatic portal system plays a crucial role in delivering nutrients and removing waste from the digestive organs.
Step-by-step explanation:
The hepatic portal system consists of the hepatic portal vein and the veins that drain into it.
The hepatic portal vein itself is relatively short, beginning at the level of L2 with the confluence of the superior mesenteric and splenic veins.
It also receives branches from the inferior mesenteric vein, plus the splenic veins and all their tributaries.
The superior mesenteric vein receives blood from the small intestine, two-thirds of the large intestine, and the stomach.
The inferior mesenteric vein drains the distal third of the large intestine, including the descending colon, the sigmoid colon, and the rectum.
The splenic vein is formed from branches from the spleen, pancreas, and portions of the stomach, and the inferior mesenteric vein.
After its formation, the hepatic portal vein also receives branches from the gastric veins of the stomach and cystic veins from the gall bladder.
The hepatic portal vein delivers materials from these digestive and circulatory organs directly to the liver for processing.