Weighing between 3. It is situated above and to the left of the stomach and below the lungs. The liver is roughly triangular and consists of two lobes: a larger right lobe and a smaller left lobe. The lobes are separated by the falciform ligament, a band of tissue that keeps it anchored to the diaphragm.
This capsule is further covered by the peritoneum, a membrane that forms the lining of the abdominal cavity. Unlike most organs, the liver has two major sources of blood. The portal vein brings in nutrient-rich blood from the digestive system, and the hepatic artery carries oxygenated blood from the heart. The blood vessels divide into small capillaries, with each ending in a lobule.
Lobules are the functional units of the liver and consist of millions of cells called hepatocytes. The liver is classed as a gland and associated with many functions. It is difficult to give a precise number, as the organ is still being explored, but it is thought that the liver carries out distinct roles. Because of the importance of the liver and its functions, evolution has ensured that it can regrow rapidly as long as it is kept healthy. This ability is seen in all vertebrates from fish to humans.
The liver is the only visceral organ that can regenerate. It can regenerate completely, as long as a minimum of 25 percent of the tissue remains. One of the most impressive aspects of this feat is that the liver can regrow to its previous size and ability without any loss of function during the growth process. In mice, if two-thirds of the liver is removed, the remaining liver tissue can regrow to its original size within 5 to 7 days. In humans, the process takes slightly longer, but regeneration can still occur in 8 to 15 days — an incredible achievement, given the size and complexity of the organ.
Over the following few weeks, the new liver tissue becomes indistinguishable from the original tissue. This regeneration is helped by a number of compounds, including growth factors and cytokines. Some of the most important compounds in the process appear to be:. An organ as complex as the liver can experience a range of problems. A healthy liver functions very efficiently. However, in a diseased or malfunctioning liver, the consequences can be dangerous or even fatal.
Fascioliasis: This is caused by the parasitic invasion of a parasitic worm known as a liver fluke, which can lie dormant in the liver for months or even years.
Fascioliasis is considered a tropical disease. Cirrhosis: This sees scar tissue replace liver cells in a process known as fibrosis.
When the liver has broken down harmful substances, its by-products are excreted into the bile or blood. Bile by-products enter the intestine and leave the body in the form of feces. Blood by-products are filtered out by the kidneys, and leave the body in the form of urine.
Health Home Conditions and Diseases. Liver: Anatomy and Functions Share on Facebook Share on Twitter Share on Linkedin Share on Pinterest Share via Email Print this Page Liver Gallbladder and Pancreas Anatomy of the liver The liver is located in the upper right-hand portion of the abdominal cavity, beneath the diaphragm, and on top of the stomach, right kidney, and intestines.
Shaped like a cone, the liver is a dark reddish-brown organ that weighs about 3 pounds. Functions of the liver The liver regulates most chemical levels in the blood and excretes a product called bile. Some of the more well-known functions include the following: Production of bile, which helps carry away waste and break down fats in the small intestine during digestion Production of certain proteins for blood plasma Production of cholesterol and special proteins to help carry fats through the body Conversion of excess glucose into glycogen for storage glycogen can later be converted back to glucose for energy and to balance and make glucose as needed Regulation of blood levels of amino acids, which form the building blocks of proteins Processing of hemoglobin for use of its iron content the liver stores iron Conversion of poisonous ammonia to urea urea is an end product of protein metabolism and is excreted in the urine Clearing the blood of drugs and other poisonous substances Regulating blood clotting Resisting infections by making immune factors and removing bacteria from the bloodstream Clearance of bilirubin, also from red blood cells.
Bile is a clear yellow or orange fluid that helps digest food. The liver controls most chemical levels in the blood. It also secretes a clear yellow or orange fluid called bile. Bile helps to break down fats, preparing them for further digestion and absorption. All of the blood leaving the stomach and intestines passes through the liver. The liver processes this blood and breaks down, balances, and creates nutrients for the body to use. It also breaks down metabolizes medicines in the blood into forms that are easier for the body to use.
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