LIVER ANATOMY AND FUNCTION Flashcards
What separates the two lobes of the liver?
The falciform ligament
What happens in the gall bladder?
Bile brains into bile ducts and then gathers in the gall bladder where it is stored and released when eating
What triggers the gall bladder to release bile?
Signals of early digestion e.g peptides released from carbohydrates trigger a release of a sphincter muscle and the contraction of the gall bladder to release bile into the common bile duct into the intestines to help emulsify fat
Describe the 3 stages in the transportation of bile?
1) Liver cells secrete bile which is collected by ducts that flow from the liver through the right and left hepatic ducts which ultimately drain into the hepatic duct
2) The common hepatic duct then joins with the cystic duct from the gallbladder to form the common bile duct
3) The common bile duct runs from the liver to the duodenum
Which two structures form the common bile duct?
The cystic duct from the gall bladder and the common hepatic duct come together to form the common bile duct
How many segments is the liver divided into and what do they each have?
- The liver has 8 segments
- Each has its own blood supply and bile drainage
What is a sinusoid and what happens here?
- Sinusoids are the capillary beds found in the liver
- Blood enters the liver via veins and arteries and mixes at the sinusoids
After blood has mixed at the sinusoids, how is it drained from the liver?
Blood is drained from the hepatic veins into the Inferior vena cava near the right atrium
Where does structural support in the liver come from?
Lots of connective tissue made from extracellular matrix gives the liver structural support
What increases when the liver cells become damaged?
There is an increase in connective tissue in places where there would normally be hepatocytes. A normal healthy liver would have minimal structural connective tissue
What is the scale of fibrosis?
- This is a scale that demonstrates the level of fibrosis of the liver
- F1 is the lowest level of fibrosis
- F4 is the highest level of fibrosis
Give 4 facts about hepatocytes
- Are the main functional and most common cells in the liver
- Very versatile
- Low mitotic index
What is the function of tight junctions in the hepatocytes?
Tight junctions to prevent bile from leaking out and damaging neighbouring hepatocytes
What is the function of the sinusoidal plane in the hepatocytes?
Sinusoidal plane of the cell faces the blood supply . Proteins and carbohydrates made by the liver can be secreted into the circulation
Describe the biliary epithelium (3)
- It forms collecting vessels to collect canalicular bile
- They have transport and secretion properties
- They gradually increase in size to form mature bile ducts
What type of cells is the liver epithelium made from and what is its function?
- Squamous epithelium cells
- Regulation of coagulation and leukocyte traffic
- They allow the selective transport of materials and things like white blood cells into the tissue
- Line the liver
- Protect The liver from blood cells, bacteria, viruses
What are Kupffer cells?
- Hepatic macrophages within the sinusoids
- Have functions related to phagocytosis and regulation of the microcirculation