three blood vessels associated with the liver
portal vein - carries nutrient rich blood from the gut,
- prevents glucose entering the general circulation by converting it to glycogen
-helps maintain osmotic potential of blood
- allows toxins to be removed
It is responsible for the breakdown of red blood cells and the production of bile salts
hepatic artery - receives oxygenated blood
hepatic vein - deoxygentaed blood is carried away from the liver
Explain the importance of bilirubin in the onset of jaundice. [4]
- comes from breakdown of red blood cells
- results from the breakdown of the heme group of hemoglobin
- normally excreted with bile
-released into blood when excess is produced or bile duct blocked
- jaundice is a yellowish pigmentation of the skin/whites of eyes caused by high levels of bilirubin in blood/tissues
- it is often observed in newborns as they have an immature liver which does not keep up with excreting bilirubin
- jaundice is often seen in liver disease such as liver cancer/chronic alcoholism
compare and contrast the structure of cappilaries and sinusoids
a. sinusoids have open pores/fenestrations and capillary does not contain fenestrations
b. Kupffer cells are located inside sinusoids but not in capillaries
c. sinusoids larger in diameter than capillaries
- both are one cell thick
- both have a basement membrane;
what does liver do with excess aminoacids?
it removes toxic amine group (-NH2) from the breakdown of aminoacids
converts it into urea
list the functions of the liver
- detoxification (by converting into less harmful substance (alcohol, -NH2) or (making substance water soluble by attaching it to another substance)
- storage of nutrients (vitamin A, D, glycogen, iron)
- control of blood glucose levels
- synthesis of cholesterol
- conversion of cholesterol into bile salts
- production of bile
- breakdown of erythrocytes
- produce plasma proteins ( proteins in the blood such as albumin which regulate osmotic potential of blood)
outline the breakdown of erythrocytes in the liver
- Kuppfer cells engulf erythrocytes and break them down into heme group and globin
- globin broken down into aminacids metabolised by the liver
- heme group broken down into bilirubin and iron
- iron either stored in the liver or transported to bone marrow
- bilirubin used to make bile
