Liver Physiology + Function

Question 1

75% blood supply to liver is from?

Answer 1

Portal vein

Question 2

25% , blood supply to liver is from?

Answer 2

Proper hepatic artery

Question 3

What brings nutrient rich blood into the liver?

Answer 3

Portal vein

Question 4

What takes oxygenated blood into the liver?

Answer 4

Proper hepatic artery

Question 5

What takes deoxygenated blood back to the vena cava?

Answer 5

Hepatic vein

Question 6

Lobules are?

Answer 6

Collection of cells
Functional unit of the liver

Question 7

Structure of hepatic lobule?

Answer 7

Hexagonal

Question 8

Sinusoids define:

Answer 8

Small blood vessels between radiating rows of hepatocytes

Question 9

Characteristics of sinusoids:

Answer 9

One cell thick
Nutrient exchange
Gaps that allow macromolecules to pass through

Question 10

Hepatic lobule consists of?

Answer 10

Portal triad
Sinusoids
Central vein ( hepatic vein)
Hepatocyte
Kupffer cell

Question 11

Portal triad

Answer 11

Bile duct
Portal vein
Hepatic artery

Question 12

Kupffercells are?,

Answer 12

Type of tissue macrophage ( performs a lot of defence functions)

Question 13

Canalinculi

Answer 13

Series of channels between cells

Question 14

How does there billiary systems structure support function?

Answer 14

Two separate blood supplies and separation of blood from bile
Massive SA for exchange of molecules
Sinusoids structure allows exchange of large solutes
Kupffer cells form a protective barrier

Question 15

Biliary system: Bile secreted by hepatocytes then…..

Answer 15

canalinculi —-> Collected by system of ducts (ductules)—->
Which drain into common hepatic duct (multiple bile duct)—-> to the common bile duct

Question 16

Bile is secreted by?

Answer 16

Hepatocytes

Question 17

Bile is a combination of?

Answer 17

Water, electrolytes, bilirubin, cholesterol and bile salts

Question 18

What is bilirubin?

Answer 18

Toxic, yellow pigment; formed by the break down of haemoglobin

Question 19

Where is bile stored?

Answer 19

Gallbladder

Question 20

Bile is secreted where? After common bile duct

Answer 20

Duodenum

Question 21

Duodenum is?

Answer 21

First part of small intestine; comes down from stomach

Question 22

Function of bile

Answer 22

Fat digestion and absorption
Elimination of waste products especially bilirubin and cholesterol

Question 23

Cholecystokinin CCK is?

Answer 23

A hormone that causes contraction of the gallbladder leading to ejection of bile into the duodenum

Question 24

When is CCK released?

Answer 24

When it detects a lot of lipid rich food

Question 25

One of the first signs of liver failure is? Why?

Answer 25

Jaundice—> due to the presence of bilirnebin in the body because it isn't being handled properly by the liver

Question 26

Enterohepatic circulation benefit

Answer 26

Gives liver first access to nutrients, toxins, medications from gut

Question 27

What % of bile salts excreted in faeces?

Answer 27

5%

Question 28

Functional unit of liver?

Answer 28

Liver lobule

Question 29

Where are kupffer cells located?

Answer 29

Sinusoidal lining

Question 30

Function of hepatocytes

Answer 30

Carry out most metabolic pathways

Question 31

Function of pit cells

Answer 31

Natural killer plus specific to liver

Question 32

Examples of blood clotting factors?

Answer 32

Fibrinogen Prothrombin other factors —> V, VI, IX, X, XII

Question 33

What is essential ( vitamin)for formation of pro-thrombin and other factors?

Answer 33

Vitamin k

Question 34

Where is vitamin k stored?

Answer 34

In the liver

Question 35

Warfarin blocks the activity of what enzyme?

Answer 35

Epoxide reductase

Question 36

How does warfarin have an anticoagulant effect on the blood?

Answer 36

Blocks epoxide reductase which means vitamin K stays in its oxidised form Hence reduced form of Vitamin K produced = fewer clotting factors

Question 37

Functions of liver

Answer 37

Bile production storage of vitamin k / A/ D/ E/ B12+ carbohydrates and lipids+ iron (stored as ferritin) Metabolism Detoxification

Question 38

Iron is stored as what in the liver?

Answer 38

Ferritin

Question 39

Function of liver= metabolism. Give examples

Answer 39

Carbohydrates - glucagon and insulin Lipids Proteins - gluconeogenesis and deamination

Question 40

Examples of cholesterol sources:

Answer 40

Dietary cholesterol —> Chylomicron remnants De novo synthesis in liver Cholesterol from extrahepatic tissue —> HDL

Question 41

Chylomicron remnants define:

Answer 41

Fat molecules that get left over from digestion process

Question 42

How are Chylomicron remnants transported into the liver?

Answer 42

Via portal vein