About the Liver
The liver is a large, triangular organ that sits in the upper right side of the abdomen and extends almost the entire width of the torso. In a healthy adult, the liver weighs approximately three pounds and has two lobes, separated by a ligament. The liver has over 500 different functions and affects several different systems within the body. As part of the digestive and excretory system, the liver has two functions: filtration and bile production.
Filtration and Bile Production
During the filtration process, the liver removes toxins and unusable materials from the blood before it can reach the rest of the body. The filtration process also removes usable materials, such as iron and some vitamins, for use in other body processes. As part of the excretory process, it filters excess amino acids and processes them into urea, a major component of urine. The liver also filters out cholesterol and combines it with filtered waste products to create bile. Bile is a green, slippery substance that emulsifies, or breaks down, fats for easy absorption in the intestinal tract. Bile also acts as a carrier for the filtered toxins from the liver, and deposits those toxins in the intestines for removal during defecation. The liver produces bile continuously and stores the bile in the gall bladder.
How the Liver Functions in Excretion
The liver connects to the digestive and excretory systems through two organs, the gall bladder and the hepatic portal vein, and works in a continuous loop. When we eat fatty foods, the liver signals the gall bladder to release bile into the intestines. The bile emulsifies the fats and deposits waste products into the intestines for elimination. The capillaries in the intestines absorb the emulsified fats into the blood stream. The blood from the capillaries drains into the hepatic portal vein and travels to the liver. The liver processes the blood, removing toxins, cholesterol, excess amino acids, iron and some vitamins. The iron is used for red blood cell production, amino acids are broken down into urea and sent to the kidneys, and the liver stores the vitamins for later use. The liver then converts the cholesterol and waste products into bile, which goes back to the gall bladder for use in the intestines.
