Liver Flashcards
How many lobes does the liver have?
What are the two liver blood supplies?
2 lobes. Left (smaller) and right (bigger)
Hepatic artery and portal vein
What is/are the functional unit(s) of the liver?
Lobule or acinus
What are the components of the liver’s functional units?
Cords: rows of hepatocytes that surround central vein.
Sinusoids: blood spaces that surround the cords and drain into central vein.
Bile canaliculi: small channels between cords that carry bile to gall bladder and gut.
What are hepatocytes and what do they do?
They are the cells of the liver who respond quickly to metabolic demands and regenerate quickly.
What is the portal triad?
It is the the part of the lobule made up of the hepatic artery, portal vein and bile duct.
List the 4 functions of the liver.
Excretory: excretes bilirubin and bile.
Synthetic: synthesizes proteins, glycogen, ketones, cholesterol.
Metabolic: metabolizes drugs, ammonia, bilirubin.
Storage: stores iron, glucose, cholesterol.
What is the major substance excreted by the liver?
Bilirubin
What is bilirubin?
It is the major bile pigment formed from the breakdown of hemoglobin when RBCs are broken down in the spleen.
What type of bilirubin is released into the blood after RBCs break down in macrophages?
Unconjugated bilirubin.
What happens to unconjugated bilirubin in the bloodstream?
Since it is insoluble, it needs to be carried to the liver’s hepatocytes by albumin.
What area of the hepatocyte is unconjugated bilirubin carried to by albumin?
The endoplasmic reticulum of the hepatocyte.
Where is bilirubin conjugated and by what?
Bilirubin is conjugated in the ER of a hepatocyte by glucuronic acid.
What does conjugation make to bilirubin?
Conjugation makes bilirubin soluble and able to be excreted from the body.
What happens to conjugated bilirubin in the intestine when passed with bile?
The bilirubin is converted to urobilinogen by the normal flora of the intestine.
What is urobilinogen oxidized to?
Urobilinogen is oxidized into stercobilin which are pigments excreted in stool that gives stool its dark color, or oxidized into urobilin after it is reabsorbed into the bloodstream and excreted as urine.
What does high conjugated bilirubin in intestine do?
Increases urobilinogen.
What is the bile?
It is the greenish liquid composed of bile acids, bile salts, and bilirubin stored in the gallbladder.
What organ secrets bile acids into the bile?
The liver.
What is involved in the processing of lipids by solubilizing them?
Bile acids
Give an example of bile acid, what it is formed from and it’s function.
Cholic acid, formed from the breakdown of cholesterol and functions as the major mechanism of cholesterol elimination in the body.
Where is bile released to after a meal?
Into the small intestine.
What do aggregates of bile acids that surround dietary fat do?
They help with digestion, solubilization and absorption of lipids.
What is the liver process with bile acids?
Bile acids are recycled, reabsorbed, attached to albumin and extracted by the liver.
What synthesizes almost all proteins? And what proteins in particular?
Hepatocytes, albumin and coag factors except immunoglobulins.