Final answer:
The hepatic portal system directs blood from parts of the gastrointestinal tract to the liver, where hepatocytes process nutrients and wastes.
Step-by-step explanation:
The hepatic portal system is a crucial component of the human circulatory system, responsible for directing blood from parts of the gastrointestinal tract to the liver. This system is unique because instead of blood immediately entering the systemic circulation, absorbed nutrients and specific wastes navigate via the hepatic portal vein to the liver, where blood flow comes predominantly from this system. The liver functions as a biochemical factory, processing nutrients, toxins, and wastes. This processing plant comprises three main components: hepatocytes, bile canaliculi, and hepatic sinusoids, with the hepatocytes accounting for approximately 80 percent of the liver's volume.
When it comes to blood flow to the liver, about 1500 mL of blood per minute travel through it at rest. A significant portion of this blood flow derives from the hepatic portal system. While the exact percentage isn't provided in the information, the architecture of the hepatic portal system suggests a major contribution to liver blood flow. The significance of the hepatic portal system's architecture lies in its ability to efficiently deliver substances absorbed from the gastrointestinal tract to the liver for metabolism and detoxification, even if the percentage extracted by the liver in one pass is low.
The liver's anatomical arrangement enhances the functions of hepatocytes; they are strategically placed in hepatic laminae radiating from the portal vein in each hepatic lobule, which allows for optimal exposure to the incoming blood containing nutrients and wastes.