Lopez_Liver+Anatomy

What is the largest internal organ in the human body?

Liver (~1.5 kg)

Where is the liver located?

Right upper quadrant beneath diaphragm, protected by ribs 7–11

What are the surfaces of the liver?

Diaphragmatic (convex, superior/anterior) and Visceral (concave, inferior, contacts stomach, colon, kidney)

What are the four anatomical lobes of the liver?

Right, Left, Caudate, Quadrate

What ligament divides the right and left lobes on the anterior surface?

Falciform ligament

What is the round ligament (ligamentum teres)?

Remnant of the fetal umbilical vein

What are the coronary ligaments?

Peritoneal reflections attaching liver to diaphragm

What percentage of blood to the liver comes from the portal vein?

~75% (nutrient-rich, low oxygen)

What percentage of blood to the liver comes from the hepatic artery?

~25% (oxygenated)

How does blood leave the liver?

Central veins → hepatic veins → inferior vena cava

What is contained in a portal triad?

Portal vein branch, hepatic artery branch, bile duct

What is the direction of blood flow in the classic lobule?

From portal triads → sinusoids → central vein

What is the direction of bile flow in the classic lobule?

From hepatocytes → canaliculi → bile duct (opposite to blood flow)

What are the three zones of the portal acinus?

Zone 1 (periportal), Zone 2 (intermediate), Zone 3 (centrilobular)

Which liver zone has the best oxygenation and nutrient supply?

Zone 1 (periportal)

Which liver zone is most susceptible to ischemia?

Zone 3 (centrilobular)

What are hepatocytes and their functions?

Cuboidal cells for metabolism, protein synthesis, and bile production

What are Kupffer cells?

Macrophages lining sinusoids, phagocytose debris and bacteria

What are stellate (Ito) cells and their function?

Cells in Space of Disse, store Vitamin A, produce collagen when activated

What type of endothelium lines hepatic sinusoids?

Fenestrated endothelium

What are bile canaliculi?

Small channels between hepatocytes that drain bile toward bile ducts

What is the Space of Disse?

Perisinusoidal space between hepatocytes and sinusoidal endothelium, site of stellate cells and fibrosis

Trace the path of bile from hepatocytes to the duodenum.

Canaliculi → bile ductules → right/left hepatic ducts → common hepatic duct + cystic duct → common bile duct → duodenum

What is the Pringle maneuver?

Clamping of the hepatoduodenal ligament (portal triad) to control liver bleeding

What are Couinaud segments?

8 functional segments of the liver, each with its own vascular inflow, outflow, and biliary drainage

Which lobe drains directly into the IVC and can hypertrophy in cirrhosis?

Caudate lobe