Liver & Gall bladder

Definition of the liver: It's the largest gland in our body which lies mainly in the upper right section of the abdominal cavity, under the diaphragm.


Structure: the liver has two main lobes, the right lobe & the smaller left lobe. It contains approximately 100,000 lobules that serve as its structural & functional units.





Liver's functions in the body:
-as the blood from the hepatic portal vein passes through the liver, it removes poisonous substances & detoxifies them.
-the liver also removes nutrients & works to keep the contents of the blood constant.
-it removes and stores iron & the fat soluble vitamins A,D,E,K, & B12.
-the liver makes the plasma proteins from amino acids.
-helps regulate the quantity of cholesterol in blood.
ex. the conversion of amino acids to glucose necessitates deamination, the removal of amino groups to form urea.
 


Liver's functions in the digestive system:
-maintains the blood glucose level at about 0.1% even though a person eats intermitently.
-when insulin is present, any excess glucose present in blood is removed & stored by the liver as glycogen.
-between meals, glycogen is broken down to glucose, which enters the hepatic veins & in this way, the blood glucose level remains constant.
-if the supply of glycogen is depleted, the liver converts glycogen ( from fats) and amino acids to glucose molecules.
-the liver produces bile, which is stored in the gall bladder.


Bile's definition:
-Bile is a yellow-green fluid that is made by the liver, stored in the gallbladder and passes through the common bile duct into the duodenum where it helps digest fat.
-The principal components of bile are cholesterol, bile salts, and the pigment bilirubin.


why does bile have a green colour?
bile has a yellowish-green colour because it contains the bile pigment bilirubin, derived from the breakdown of hemoglobin, the red pigment of red blood cells.


Definition of gall bladder:
-is a pear shaped, muscular sac attached to the surface of the liver.
-about 1000 ml of bile are produced by the liver each day, any excess is stored in the gall bladder.
-water is re-abosorbed by the gall bladder so that bile becomes a thick, mucus like material.
-when needed, bile leaves the gall bladder and proceeds to the duodenum via the common bile duct.
-cholesterol content of bile can come out of solution and forms crystals.
-if the crystal grows in size, they form gall stones.


By: Rojin, Nicole, Sarah, Fred