The Liver

Question 1

The function lobe of the liver is…

Answer 1

… the bottom right lobe

Question 2

The structural support for the liver is provided by…

Answer 2

1) the inferior vena cava (Three veins)
2) ligaments connected to the diaphragm
3) falicform ligament connected to the front of the abdominal wall

Question 3

The main blood supply to the liver is the…

Answer 3

Hepatic portal vein

Question 4

The hepatic portal vein is supplied by…

Answer 4

1) splenic vein
2) inferior mesenteric vein
3) jejunal and ileal veins
4) superior mesenteric veins

Question 5

The inferior mesenteric vein is supplied by the…

Answer 5

1) rectum
2) sigmoid colon
3) descending colon

Question 6

The superior mesenteric vein is supplied by…

Answer 6

1) small intestine
2) caecum
3) ascending colon
4) transverse colon

Question 7

_______ produces ___ litre(s) of bile daily

Answer 7

Gall bladder, 1

Question 8

The _______ stores ____ml of unneeded bile which then enters the _________

Answer 8

Duodenum, 50ml, umpulla revata

Question 9

The portal system is made out of which two systems and how are they connected?

Answer 9

1) hepatic portal system
2) hypothalamo-hypophyseal portal system

Connected in series

Question 10

What is carried in the portal system (there are 7 “things”)

Answer 10

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)

Question 11

The liver is the only organ to complete what cycle?

Answer 11

Urea cycle

Question 12

Types/Things that assault the body (there is a long list but this one includes 7 things)

Answer 12

1) chemicals (called toxins if they are biological)
2) bacteria
3) viruses
4) protozoa
5) nematodes (roundworms)
6) cestodes (tapeworms)
7) trematodes (flukes)

Question 13

What is NOT in the portal vein?

Answer 13

Lipids

Fat soluble vitamins (A, D, E, K)

Question 14

What happens to fats?

Answer 14

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)

Question 15

Functions of the liver (9 functions/capabilities)

Answer 15

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

Question 16

What is stored in the liver?

Answer 16

1) Glycogen
2) Lipoprotein
3) Triglycerides
4) Iron
5) Vitamin A, D, B12, K

Question 17

What are the main dietary lipids?

Answer 17

Triglycerides
Cholesterol
Phospholipids

Question 18

Anabolic processes/molecules (made) in the liver (4)

Answer 18

1) Plasma proteins (albumin, coagulation factors)
2) Complement proteins of the immune system
3) Glycogen
4) Haematopoiesis as foetus

Question 19

What happens if adult bone marrow isnt functioning?

Answer 19

Haematopoiesis in the liver (occurred as foetus)

Question 20

What catabolic processes occur in the liver?

Answer 20

Drug breakdown (using cytochrome P450)
Hormones
Haemoglobin
Poisons
Removal of aged red blood cells (after splenectomy)

Question 21

When does the liver need to remove aged erythrocytes?

Answer 21

After a splenectomy

Question 22

Endocrine functions of the liver?

Answer 22

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)

Question 23

What cells constitute 80% of the liver cell population?

Answer 23

Hepatocytes

Question 24

At what speed do hepatocytes regenerate?

Answer 24

Remarkably fast

Question 25

What do hepatocytes contain that some other cells dont? (7 things)

Answer 25

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

Question 26

Shape of sinusoids??

Answer 26

Irregular tubular space (for passage of blood)

Question 27

What do sinusoids replace and where in the body are they found, and what’s special about its endothelium?

Answer 27

Replace capillaries and venules
Found in the liver, spleen and bone marrow
Endothelial cells have large gaps

Question 28

What makes up a portal triad?

Answer 28

Arteriole
Venue
Bile duct

Question 29

Journey of lymphatic vessels in the liver

Answer 29

Arise from the periportal space of Mall
Drain into the liver hilum
Move onto thoracic duct

Question 30

What are kupffer cells, what are they derived from, where are they found and what % of body tissue are they?

Answer 30

Specialist macrophages
Derived from monocytes
Form the lining of sinusoids
Constitute 80% of tissue macrophages in the body

Question 31

What is special about stellate (Ito) cells?

Answer 31

They are full of cytoplasmic vacuoles containing vitamin A

Question 32

What is the main source of vitamin A in the diet?

Answer 32

Fish liver oils

Question 33

What causes/happens in liver cirrhosis and what is the consequence?

Answer 33

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