Download H4 Functions of the liver – summary of mark schemes

H4 Functions of the liver – summary of mark schemes
H.4.1
Outline the circulation of blood through liver tissue, including the hepatic artery, hepatic portal vein, sinusoids and hepatic vein.
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H.4.3
(oxygenated) blood from heart to liver via hepatic artery;
hepatic artery from aorta brings blood to liver;
hepatic portal vein (from gut) brings blood to the liver;
incoming blood flows merge in sinusoids of liver;
sinusoids are liver capillaries;
sinusoids merge to form hepatic vein;
hepatic vein carries blood away from liver to vena cava;
hepatic artery (carries O2) into liver;
(nutrient laden) blood carried from intestines through hepatic portal vein;
artery / hepatic portal vein divide (eventually) into sinusoids;
sinusoids drain into (branches of) hepatic vein;
blood leaving the liver departs through the hepatic vein;
Outline the role of the liver in the storage of nutrients, including carbohydrate, iron, vitamin A and vitamin D.
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H.4.6
liver stores excess glucose as glycogen / releases glucose from glycogen (as levels drop);
liver breaks down red blood cells / hemoglobin and stores iron;
liver stores fat soluble vitamins / vitamin A / vitamin D / vitamin B12 / folic acid;
Describe the process of erythrocyte and hemoglobin breakdown in the liver, including phagocytosis, digestion of globin and bile
pigment formation.
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erythrocytes rupture when they reach the end of their life span / after 120 days;
absorbed by phagocytosis / Kupffer cells in liver from blood;
Kupffer cells found lining sinusoids in liver;
hemoglobin split into globin and heme groups;
iron removed from heme leaving bile pigment / bilirubin;
bilirubin released into alimentary canal;
digestion of globin to produce amino acids;