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The liver (hepar) is an extremely important organ in the body of mammals and vertebrates as it provides functions essential for life. It is the largest internal organ and has numerous functions including production of bile and protein, fat and carbohydrate metabolism. During foetal development, the liver has an important haemopoetic function, producing red and white blood cells from tissue between the hepatic cells and vessel walls.
 
The liver (hepar) is an extremely important organ in the body of mammals and vertebrates as it provides functions essential for life. It is the largest internal organ and has numerous functions including production of bile and protein, fat and carbohydrate metabolism. During foetal development, the liver has an important haemopoetic function, producing red and white blood cells from tissue between the hepatic cells and vessel walls.
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The size of the liver varies due to its role in metabolism. In carnivores the liver weighs about 3-5% of body weight, in omnivores 2-3% and in herbivores 1.5%. the liver is much heavier in young animals than older animals as it atropies with age.
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The size of the liver varies due to its role in metabolism. In carnivores the liver weighs about 3-5% of body weight, in omnivores 2-3% and in herbivores 1.5%. the liver is much heavier in young animals than older animals as it atrophies with age.
    
The liver is derived from an outpocketing of endoderm epithelium on the ventral duodenum from the caudal part of the foregut. The connection to the gut narrows to become the bile duct. The parenchymal tissue of the liver is formed from proliferating epithelial cords or strands which integrate with the blood sinuses of the umbilical and vitelline veins.
 
The liver is derived from an outpocketing of endoderm epithelium on the ventral duodenum from the caudal part of the foregut. The connection to the gut narrows to become the bile duct. The parenchymal tissue of the liver is formed from proliferating epithelial cords or strands which integrate with the blood sinuses of the umbilical and vitelline veins.