Liver is the largest gland in the body, situated on the right side of the abdominal cavity just below the diaphragm. Mitochondria are present in maximum number in liver, which emphasizes that liver is involved in many biochemical reactions. There are various important functions of liver in our body. In various functions the main role of liver is to participates in the metabolic reactions.
FUNCTION OF LIVER:
- SECRETION: Liver acts as an exocrine gland and secretes bile from the hepatocytes, which is stored in the gallbladder temporarily. Then it passes through the bile duct to the lumen of the duodenum. Bile is mainly important for digestion and absorption of fat.
- ROLE IS METABOLIC REACTION: Liver is the key organism where the metabolism of carbohydrates, lipids and proteins take place. It is also involved in the metabolism of vitamin and minerals.
- a. ROLE IN CARBOHYDRATE METABOLISM: Liver helps in carbohydrate metabolism and control the glucose level in blood. It does this in three ways- A. Glucose in the blood transformed into glycogen through the process Glycogenesis and stored in the liver, B. The breakdown of liver glycogen into glucose through Glycogenolysis, C. The formation of glucose from non-carbohydrate sources like protein, fat etc.
- b. ROLE IN FAT METABOLISM: Liver also plays a vital role in degradation and synthesis of fat. It contains enzyme lipoprotein lipase which hydrolyses triglycerides, cholesterol, and phospholipid into fatty acids. Liver also synthesizes triglycerides from carbohydrate and cholesterol and phospholipids from unused fatty acids.
- c. ROLE IN PROTEIN METABOLISM: Liver brings about the deamination of amino acids which is very essential for energy production. It is the main site of urea formation and the site of formation of non-essential amino acids. d. Liver also helps in transamination by converting the nitrogen group of an amino acid into carbohydrate.
- EXCRETORY FUNCTION: Liver acts as associative excretory organ. In the deamination process ammonia is produced from proteins, which is a very harmful substance for our body. And with bile some toxic substance, microbes and unwanted part of some medicine are excreted from the body.
- PROTECTIVE FUNTION: Liver contain Kupffer cells (macrophage cell) are endothelial cells lined the blood sinusoid which efficiently remove bacteria and other foreign particles from the portal circulation by the process of phagocytosis. It helps to clean the blood. Liver also detoxified some drugs by oxidation by hydrolysis.
- Liver also acts as the storage of glucose (in the form of glycogen), vitamin B12 and vitamin A and also the iron storage medium.
- Liver is the site for synthesis of plasma proteins, some blood coagulation factor like- Prothrombin (liver cells help to convert the inactive pre-prothrombin to active prothrombin in the presence of vitamin-K), Fibrinogen and some other clotting factor such as- factor V, VII, IX, and X. It also synthesizes some enzymes such as Alkaline phosphatase, Serum glutamic oxaloacetic transaminase (SGOT). Liver helps to synthesize urea, and some times it synthesizes cholesterol from the active acetate.
- Liver also helps to regulate our body temperature by producing heat from various metabolic reactions.
Liver plays many other functions such as detoxification, miscellaneous formation. It is an important site for erythropoiesis.
NOTABLE: For its vital role in most of the chemical metabolic reaction of our body liver is also known as the- Chemical Laboratory Of The Body.