The Liver Flashcards
The function lobe of the liver is…
… the bottom right lobe
The structural support for the liver is provided by…
1) the inferior vena cava (Three veins)
2) ligaments connected to the diaphragm
3) falicform ligament connected to the front of the abdominal wall
The main blood supply to the liver is the…
Hepatic portal vein
The hepatic portal vein is supplied by…
1) splenic vein
2) inferior mesenteric vein
3) jejunal and ileal veins
4) superior mesenteric veins
The inferior mesenteric vein is supplied by the…
1) rectum
2) sigmoid colon
3) descending colon
The superior mesenteric vein is supplied by…
1) small intestine
2) caecum
3) ascending colon
4) transverse colon
_______ produces ___ litre(s) of bile daily
Gall bladder, 1
The _______ stores ____ml of unneeded bile which then enters the _________
Duodenum, 50ml, umpulla revata
The portal system is made out of which two systems and how are they connected?
1) hepatic portal system
2) hypothalamo-hypophyseal portal system
Connected in series
What is carried in the portal system (there are 7 “things”)
1) water
2) water soluble minerals
3) electrolytes (sodium, potassium, chloride, bicarbonate, calcium, magnesium, iron)
4) carbohydrates (glucose, galactose, fructose)
5) proteins (amino acids, dipeptides, tripeptides)
6) intestinal hormones (particularly pancreatic hormones)
7) toxins (including ammonia)
The liver is the only organ to complete what cycle?
Urea cycle
Types/Things that assault the body (there is a long list but this one includes 7 things)
1) chemicals (called toxins if they are biological)
2) bacteria
3) viruses
4) protozoa
5) nematodes (roundworms)
6) cestodes (tapeworms)
7) trematodes (flukes)
What is NOT in the portal vein?
Lipids
Fat soluble vitamins (A, D, E, K)
What happens to fats?
Digested by lipases (needs bile to form micelles)
Absorbed into cells and processed into chylomicrons
Chylomicrons are taken up by lacteals in the lymphatic system that contain chyme (lymph and chylomicron mixture)
Lacteals drain into the abdominal lymphatic vessels into the thoracic duct which joins the venous system at the junction of the left internal jugular vein and subclavian veins (chylomicrons can enter via hepatic portal vein)
Functions of the liver (9 functions/capabilities)
1) Storage
2) protein production (albumin)
3) detoxification (cytochrome P450)
4) Bile production
5) Anabolism
6) Catabolism
7) Filtering (Kupffer cells are critical for this)
8) Exocrine (one litre of bile)
9) Endocrine
What is stored in the liver?
1) Glycogen
2) Lipoprotein
3) Triglycerides
4) Iron
5) Vitamin A, D, B12, K
What are the main dietary lipids?
Triglycerides
Cholesterol
Phospholipids
Anabolic processes/molecules (made) in the liver (4)
1) Plasma proteins (albumin, coagulation factors)
2) Complement proteins of the immune system
3) Glycogen
4) Haematopoiesis as foetus
What happens if adult bone marrow isnt functioning?
Haematopoiesis in the liver (occurred as foetus)
What catabolic processes occur in the liver?
Drug breakdown (using cytochrome P450) Hormones Haemoglobin Poisons Removal of aged red blood cells (after splenectomy)
When does the liver need to remove aged erythrocytes?
After a splenectomy
Endocrine functions of the liver?
1) Release of angiotensin (peptide hormone that causes vasoconstriction to raise blood pressure)
2) Modifies vitamin D to its active form
3) Breaks down hormones (eg oestrogen)
What cells constitute 80% of the liver cell population?
Hepatocytes
At what speed do hepatocytes regenerate?
Remarkably fast
What do hepatocytes contain that some other cells dont? (7 things)
1) Numerous mitochondria
2) A lot of peroxisomes
3) Numerous free ribosomes
4) A lot of RER
5) A lot of SER
6) Numerous Golgi complexes
7) Glycogen deposits
Shape of sinusoids??
Irregular tubular space (for passage of blood)
What do sinusoids replace and where in the body are they found, and what’s special about its endothelium?
Replace capillaries and venules
Found in the liver, spleen and bone marrow
Endothelial cells have large gaps
What makes up a portal triad?
Arteriole
Venue
Bile duct
Journey of lymphatic vessels in the liver
Arise from the periportal space of Mall
Drain into the liver hilum
Move onto thoracic duct
What are kupffer cells, what are they derived from, where are they found and what % of body tissue are they?
Specialist macrophages
Derived from monocytes
Form the lining of sinusoids
Constitute 80% of tissue macrophages in the body
What is special about stellate (Ito) cells?
They are full of cytoplasmic vacuoles containing vitamin A
What is the main source of vitamin A in the diet?
Fish liver oils
What causes/happens in liver cirrhosis and what is the consequence?
Hepatic stellate cells lose their vitamin A storage capability and differentiate into myofibroblasts that synthesise and deposit collagen within the perisinusoidal space, leading to liver fibrosis
Collagen surrounds the central vein, constricting it which leads to portal hypertension
