PCOL838: LIVER DISEASES EXAM 2025
QUESTIONS AND ANSWERS
Anatomy of liver
-Wrapped in tough fibrous capsule, covered by visceral peritoneum, divided into 2 lobes (left
and right)
-Can be differentiated functionally via the portal blood flow into 4 sectors, which are further
divided into 8 segments
Blood flow in liver
-Hepatic portal system: the central veins receive dual blood supply from hepatic portal vein
(~75%) and hepatic arteries (~25%)
Portal vein/Hepatic artery → Central vein → Hepatic vein → Inferior vena cava
-Hepatic portal vein: carries venous blood drained from the spleen, GI tract, and pancreas
-Hepatic arteries: one of the final branches of the celiac artery, supply arterial blood to the liver
-Central veins: AKA terminal veins or hepatic venules
Cells of the liver
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,Hepatocytes:
-Liver cells
-Function: metabolism
Cholangiocytes:
-Biliary epithelial cells
Function: line the bile duct; secretion
Kupffer cells:
-Stellate macrophages
-Function: phagocytosis of pathogens and particles (dead cells)
Stellate cells:
-Ito cells, lipocytes
-Function: vitamin A storage
Sinusoidal endothelial cells:
-Endothelial cells
-Function: filtering system
Hepatic lobule
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, -Hexagonal-shaped structure composed of hepatocytes that radiate outward from a central
vein
-Anatomical unit
-Blood enters the lobules through branches of the portal vein and proper hepatic artery, then
flows through sinusoids
Hepatic acinus
-An oval mass that includes operations of two neighboring hepatic lobule. It is defined by the
branches of the portal triad
-Functional unit, blood flow and metabolic
-Zone 1: periportal, more susceptible to damage from toxins carried to the liver in the hepatic
portal vein
-Zone 2: mid, gradient of CYP enzymes
-Zone 3: centrilobular, more susceptible to ischemic (not enough blood) damage, greatest
expression of CYP enzymes
-CYP enzymes immunostained with antibodies against CYP3A4 (brown stain)
Apical and Basolateral membranes
-Apical (towards the lumen)
-Basolateral (away from lumen)
Liver functions
3 @COPYRIGHT THESTAR 2025/2026
QUESTIONS AND ANSWERS
Anatomy of liver
-Wrapped in tough fibrous capsule, covered by visceral peritoneum, divided into 2 lobes (left
and right)
-Can be differentiated functionally via the portal blood flow into 4 sectors, which are further
divided into 8 segments
Blood flow in liver
-Hepatic portal system: the central veins receive dual blood supply from hepatic portal vein
(~75%) and hepatic arteries (~25%)
Portal vein/Hepatic artery → Central vein → Hepatic vein → Inferior vena cava
-Hepatic portal vein: carries venous blood drained from the spleen, GI tract, and pancreas
-Hepatic arteries: one of the final branches of the celiac artery, supply arterial blood to the liver
-Central veins: AKA terminal veins or hepatic venules
Cells of the liver
1 @COPYRIGHT THESTAR 2025/2026
,Hepatocytes:
-Liver cells
-Function: metabolism
Cholangiocytes:
-Biliary epithelial cells
Function: line the bile duct; secretion
Kupffer cells:
-Stellate macrophages
-Function: phagocytosis of pathogens and particles (dead cells)
Stellate cells:
-Ito cells, lipocytes
-Function: vitamin A storage
Sinusoidal endothelial cells:
-Endothelial cells
-Function: filtering system
Hepatic lobule
2 @COPYRIGHT THESTAR 2025/2026
, -Hexagonal-shaped structure composed of hepatocytes that radiate outward from a central
vein
-Anatomical unit
-Blood enters the lobules through branches of the portal vein and proper hepatic artery, then
flows through sinusoids
Hepatic acinus
-An oval mass that includes operations of two neighboring hepatic lobule. It is defined by the
branches of the portal triad
-Functional unit, blood flow and metabolic
-Zone 1: periportal, more susceptible to damage from toxins carried to the liver in the hepatic
portal vein
-Zone 2: mid, gradient of CYP enzymes
-Zone 3: centrilobular, more susceptible to ischemic (not enough blood) damage, greatest
expression of CYP enzymes
-CYP enzymes immunostained with antibodies against CYP3A4 (brown stain)
Apical and Basolateral membranes
-Apical (towards the lumen)
-Basolateral (away from lumen)
Liver functions
3 @COPYRIGHT THESTAR 2025/2026
