Liver Structure and Function

Question 1

How much does the liver weigh?

Answer 1

1.4 kg

Question 2

Where is the liver located?

Answer 2

In the upper right quadrant of the abdomen tucked against the inferior surface of the diaphragm

Question 3

What are the 2 major lobes of the liver?

Answer 3

Right and left

Question 4

What are the 2 minor lobes of the liver?

Answer 4

Caudate and quadrate

Question 5

Entry/ exit of blood vessels, lymphatic vessel, ducts and nerves is via what?

Answer 5

Porta on inferior surface

Question 6

What blood vessels enter/exit the liver?

Answer 6

• Hepatic portal vein

- Hepatic artery

Question 7

What ducts enter/exit the liver?

Answer 7

• Right hepatic duct
• Left hepatic duct
• Common hepatic duct

Question 8

What nerves enter/exit the liver?

Answer 8

Hepatic nerve plexus

Question 9

Describe the formation of ducts between the liver, gallbladder and pancreas.

Answer 9

• Right and left hepatic ducts join to form common hepatic duct
• Common hepatic duct joins with cystic duct to form common bile duct
• Common bile duct joins with main pancreatic duct and enters duodenum at the major duodenal papilla

Question 10

What is the liver covered by?

Answer 10

-Connective tissue capsule and visceral peritoneum except for bare area

Question 11

What is the bare area of the liver?

Answer 11

Small area on diaphragmatic surface surrounded by coronary ligament

Question 12

What happens to the connective tissue capsule at the porta?

Answer 12

Leads to branching network of septa for support

Question 13

What doe the vessels, ducts and nerves follow through the liver?

Answer 13

Septa

Question 14

How does the septa divide the liver?

Answer 14

Into hexagonal lobules

Question 15

What are the 3 components of the hepatic triad?

Answer 15

• Hepatic portal vein
• Hepatic artery
• Hepatic duct

Question 16

Where is the portal triad located?

Answer 16

At each corner of hexagonal lobule

Question 17

What are the central veins at the centre of each lobule?

Answer 17

Hepatic veins which drain into the IVC

Question 18

How are hepatic cords arranged?

Answer 18

Radiate out from central veins

Question 19

What are hepatic cords composed of?

Answer 19

Hepatocytes

Question 20

What are hepatocytes?

Answer 20

Functional cells of the liver

Question 21

What lies between the cells within each cord?

Answer 21

Bile canaliculus (cleft like lumen)

Question 22

What are the spaces between hepatic cords?

Answer 22

Hepatic sinusoids (blood channels)

Question 23

slide 7

Answer 23

slide 7

Question 24

What is the alimentary role of the liver?

Answer 24

Production and secretion of bile

Question 25

What are the 6 components of bile?

Answer 25

- Bile acids - Lecithin - Cholesterol - Bile pigments - Toxic metals - Bicarbonate

Question 26

Where are bile salts, lecithin and cholesterol synthesised?

Answer 26

Liver

Question 27

What do bile salts, lecithin and cholesterol do?

Answer 27

Solubilise fats

Question 28

What happens to toxic metals in the liver?

Answer 28

Detoxified

Question 29

What is the function of bicarbonate?

Answer 29

Neutralisation of acid chyme

Question 30

What secretes bicarbonate?

Answer 30

Duct cells

Question 31

What secretes bile acids, lecithin, cholesterol bile pigments and toxic metals?

Answer 31

Hepatocytes

Question 32

What are bile pigments?

Answer 32

Breakdown products of haemoglobin from old/damaged erythrocytes

Question 33

What produced yellow bile?

Answer 33

Bilrubin extracted from blood by hepatocytes and secreted into bile

Question 34

What produces brown faeces?

Answer 34

Bilrubin modified by bacterial enzymes leads to brown pigments

Question 35

What produces yellow urine?

Answer 35

Reabsorbed bilirubin excreted in urine

Question 36

How are bile acids produced?

Answer 36

Synthesised in liver from cholesterol

Question 37

What happens before bile acids are secreted?

Answer 37

Bile acids conjugated with glycine or taurine to form bile salts to increase solubility

Question 38

How are secreted bile salts recycled?

Answer 38

Via enterohepatic circulation

Question 39

Describe the movement of bile salts.

Answer 39

- Liver - Bile duct - Duodenum - Ileum - Hepatic portal vein - Liver

Question 40

What is the gallbladder?

Answer 40

Saclike structure on inferior surface of liver

Question 41

What are the 3 layers in the wall of the gallbladder?

Answer 41

- Mucosa - Muscularis - Serosa

Question 42

What is the function of the mucosa?

Answer 42

It is folded in rugae for expansion

Question 43

What is the function of the muscularis?

Answer 43

Smooth muscle for contraction

Question 44

What is the serosa?

Answer 44

Connective tissue

Question 45

What are the relations of the gallbladder?

Answer 45

- Gallbladder - Cystic duct - Common bile duct

Question 46

What does the sphincter of Oddi control?

Answer 46

Controls release of bile and pancreatic juice into duodenum

Question 47

What happens when the sphincter of Oddi is contracted?

Answer 47

Bile is forced back into the gallbladder

Question 48

What does the gallbladder do to bile?

Answer 48

Concentrates bile 5-20 times (absorbs Na and H2O)

Question 49

What does fat in the duodenum result in?

Answer 49

Release of CCK

Question 50

What does the release of CCK result in?

Answer 50

- Sphincter of Oddi relaxes | - Gallbladder contracts

Question 51

What does discharge of bile into the duodenum?

Answer 51

Fat solubilisation

Question 52

Summary of secretin action.

Answer 52

- Acid in duodenum - Release of secretin - Decrease in gastric acid secretion - Decrease in gastric emptying - Increase duodenal bicarbonate secretion - Increase pancreatic bicarbonate secretion - Increase bile duct bicarbonate secretion - Neutralisation - Inhibits secretin secretion

Question 53

Summary of CCK action

Answer 53

- Fat/amino acids in duodenum - CCK release - Decrease in gastric emptying - Increase in pancreatic enzyme secretion - Gallbladder contraction - Relaxation of sphincter of Oddi - Digestion