Liver structure and function Flashcards
1
Q
What are the 4 lobes of the liver?
A
- Right
- Left
- Caudate
- Quadrate
2
Q
Describe the porta
A
- Vessels: Portal vein and hepatic artery
- Lymph vessels
- Ducts: R and L hepatic duct→ common bile duct + pancreatic duct→ sphincter of Oddi
- Nerves: hepatic nerve plexus
3
Q
Describe the septa
A
- Branching network
- Support
- Separates hexagonal shaped lobules
- Vessels, ducts and nerves follow septa
4
Q
Describe the lobules
A
- Portal triad (hepatic duct, portal vein and hepatic artery) at each corner
- Central vein→ hepatic vein→ IVC
- Hepatic cords (radiate from central vein) that are hepatocytes and within each cord are canaliculars (cleft like lumen)
- Hepatic sinusoids are the blood channels right next to the hepatic cords
5
Q
What are the jobs of hepatocytes
A
- Bile secretion
- Bile pigmentation: bilirubin (from glucose)
- Nutrient storage
- Nutrient interconversions
- Detoxification
6
Q
What is the function of ducts
A
Secrete bicarbonate in response to secretin
7
Q
What is the composition of bile?
A
- Bile acids
- Lecithin
- Cholesterol
- Bile pigments
- Toxic metals
- Bicarbonate
1-5 are secreted by hepatocytes
8
Q
What is the function of bile?
A
To breakdown lipids (fat solubilisation)
9
Q
What are the mechanisms controlling the storage and the release of bile?
A
- Stored in the bile ducts
- When sphincter of Oddi is closed, bile builds up into the gallbladder
- Gallbladder then concentrates bile 5-20x (depending on how long)
- If CCK is released then the sphincter of Oddi relaxes and smooth muscle of the gallbladder contracts
- CCK also deals with pancreatic enzyme secretion and decreasing gastric emptying and is triggered by fat/ amino acids in the duodenum
10
Q
What are the three layers of the gallbladder?
A
Mucosa (rugae), muscularis (smooth) and serosa (connective tissue)
