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:::Index>Profound Human World>Knowledge Acquisition>Nutrient Supply> The
Energy-transformed Factory
The Energy-transformed Factory
The liver of an adult is about 1.4 kg and is the biggest gland in the human body. It is
not only the digestive organ but also the blood sugar bank of the human body.
Fig.1：Liver
Liver can be divided into the right leaf and the left leaf, each of them is formed with
the liver lobule that is the functional unit of the liver and all contain the liver artery,
hepatic portal venous branches and bile duct.
The liver cells produce about 800~1000 ml bile that is fulvous liquid with pH 7.6~8.6.
The bile contains most part of the water and other substances such as bile salt,
bilirubin and etc. The bile salt can emulsify the lipid for being decomposed to the
smaller lipid droplets, which is helpful to the lipid digestion. Besides, the liver also
performs other functions as following:
1. Saccharide metabolism： The liver is important to maintain the blood sugar
homeostasis. When the blood sugar concentration in the blood becomes higher, the
liver will translate the glucose to the liver sugar for storing in the liver; when the
blood sugar becomes deficient, the river can decompose the stored liver sugar to the
blood to increase the blood sugar contraction.
2. Storage：The liver can store the liver sugar, vitamin A、B12、D、E、K, copper and
iron.
3. The liver can translate the toxic ammonia caused by the protein metabolism to the
urea to be further excreted out of the body by excretion.
4. Detoxification：Besides the ammonia, the liver also can remove the drugs such as
penicillin and sulfanilamide out the body.
5. Excretion : The blood cells are metabolized in the liver to become bilirubin that is
further secreted to the gall and decomposed by the bacteria in the intestines, finally
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be excreted with the feces.
6. Blood filtration: Part of the endothelial cells in the liver can engulf the old blood
cells and some of the bacteria.
The gall secreted by the liver are conveyed to and store in the gallbladder which is
about 7~10 cm length and can store and condense the bile for further being conveyed
to the duodenum by the common bile duct when necessary.
Reviewed by：Zhang, Yong-Ta、Lu, Yu-Ling profes
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