Liver Structure & Function Flashcards
In what section of the abdomen is the liver found?
The upper right quadrant
Name the 4 lobes of the liver
Major - Right & left
Minor - Caudate & Quadrate
Where do structures enter and leave the liver?
A section on the inferior surface called the porta hepatis. Basically a fissure about 5cm long.
What structures enter/exit the liver at the porta hepatis?
(o) Blood - Hepatic artery + portal vein
(o) Lymphatics
(o) Left & Right Hepatic Ducts
(o) Nerves - hepatic nerve plexus
Explain the passage of bile from the liver to the duodenum?
- -> Bile Canaliculus
- -> R + L hepatic duct
- -> Common hepatic duct
- -> Joins Cystic Duct = Common bile duct
- -> Joins pancreatic duct = hepatopancreatic ampulla
- -> Passes through sphincter of Oddi & major duodenal papilla
What covers the liver.
Visceral Peritoneum & connective tissue capsule
Except at the bare area
What is the bare area?
A small area on the liver’s diaphragmatic surface surrounded by the coronary ligament
What happens to the connective tissue capsule at the porta hepatis?
it forms a branching network of septa passin into the liver to support it.
Vessels, ducts & nerves follow these septa.
These septa divide the liver into hexagonal lobules
How does the portal triad relate to the lobules of the liver?
Each hexagonal lobule has a branch of the hepatic portal vein, artery and duct at its corners.
Explain the structure of the hexagonal lobules of the liver?
1) Central Vein at the centre
2) Hepatic cords of hepatocytes radiating out from central vein
3) Lumen called bile canaliculus runs between the cords
4) blood channels called hepatic sinusoids also run between cords
explain the passeage of bile
Bile salts secreted by hepatocytes
- -> Into bile canaliculi
- -> Into bile ductules
- -> Into Hepatic Ducts
- -> Common hepatic duct
- -> Merge with cystic Duct to become common bile duct
- -> Merge with pancreatic duct to become hepatopancreatic ampulla
- -> Passes through sphincter of Oddi and out the major duodenal papilla into duodenum
where do the hepatic sinusoids drain from/to? and whats their purpose?
they drain blood from the hepatic portal vein & artery, through the sinusoids and into the central vein.
They allow all the hepatocytes to be in contact with the blood and do their stuff
Where do the central veins run to?
The hepatic veins
What is the function of hepatocytes?
- Bile Synthesis
- Nutrient Storage
- Nutrient Interconversion
- Detoxification
- Storage of glycogen, fat, vitamins and mineral (e.g. copper & iron)
What are the components of bile and their sources?
Synthesized in Liver:
- Bile Acids
- Lecithin
- Cholesterol
Parts of broken haemoglobin:
- Bile Pigments (bilirubin)
Taken from blood during detoxification in liver:
- Toxic Metals
Produced in ductal cells:
- Bicarbonate