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The Liver
abdominal aorta
inferior vena cava
hepatic veins
liver
al
he
tic
a
p
rt
po
m
te
s
sy
right and left hepatic duct
(bile ducts)
hepatic arteries (right and left)
gall
bladder
hepatic artery
celiac trunk
common hepatic artery
superior mesenteric artery
hepatic
portal
vein
blood from the
digestive organs
sinusoids
(blood-filled
spaces)
hepatocytes
(liver cells)
central vein
hepatic artery portal triad
portal vein
(portal tract)
bile duct
liver
lobule
inferior
vena cava
hepatic artery
portal triad
portal vein
(portal tract)
bile duct
©Sheri Amsel
www.exploringnature.org
Function and Structure of the Liver
The liver is one of the most important organs of the body. It’s functions include:
1) Receiving venous blood from the digestive tract (oxygen poor but nutrient rich) via the portal vein, which
and is then filtered.
2) The liver makes bile (more specifically: it’s hepatocyte cells make bile). Bile is a fat emulsifier. Bile breaks
down fats so that they can be absorbed into the blood in the small intestine.
2) The liver stores glucose as glycogen and coverts the glycogen back to glucose when the body needs it.
3) The liver filters alcohol and drugs from the blood (detoxifies).
4) The liver stores fat-soluble vitamins (Vit. A, Vit. E, Vit. D, and Vit. K).
5) The liver reuses iron in old, worn out red blood cells before breaking them down.
6) The liver converts ammonia in to urea (which the body can use).
7) The liver’s cells (hepatocytes) use amino acids to make plasma proteins.
Liver Structure:
The liver has four lobes which are made up of smaller lobules. The liver’s lobules are its functional units.
Each lobule is a hexagon shape made up of plates of hepatocytes (special epithelial cells).
The plates of hepatocytes radiate outward from a central vein. Through them is a canal where the bile they
produce flows outward into the triad’s bile duct. The canals are called bile canaliculi.
At each of the 6 corners of the hexagon-shaped lobules is a triad of vessels, including:
• hepatic artery (brings arterial blood to the actual liver tissue)
• portal vein (brings venous blood to the liver to be filtered)
• bile duct
(delivers bile for fat emulsification)
Between the hepatocyte plates are sinusoids (blood-filled spaces). The sinusoids are lined with special
phagocytic cells, called Kupffer Cells. Blood from the hepatic portal vein and the hepatic artery filters through
the sinusoids from the triads to the central vein. The Kupffer Cells absorb the blood waste as it passes in the
blood.
©Sheri Amsel
www.exploringnature.org
sinusoids
(blood-filled spaces)
central vein
Liver Lobule
hepatic artery
portal vein
bile duct
liver
lobule
portal triad
(portal tract)
hepatocytes
(liver cells)
sinusoids
(blood-filled
spaces)
hepatic artery
portal vein
central
vein
bile duct
portal triad
(portal tract)
Kupffer cell
in a sinusoid
bile
canaliculi
plates of
hepatocytes
(liver cells)
©Sheri Amsel
www.exploringnature.org