Which vein primarily drains the blood from the intestine to the liver?

The superior mesenteric vein plays a crucial role in draining blood from the small intestine and part of the large intestine. It collects nutrient-rich blood from the jejunum, ileum, cecum, ascending colon, and part of the transverse colon. This vein then merges with the splenic vein to form the portal vein, which carries the combined blood supply directly to the liver. The liver then processes the nutrients, detoxifies harmful substances, and regulates blood composition.

Understanding the superior mesenteric vein's function is fundamental to comprehending the body's gastrointestinal and hepatic circulation. It highlights the importance of the portal system in nutrient absorption and metabolism, which is vital for maintaining homeostasis in the body.