Gall-bladder and Liver physiology

Question 1

Which lobe of the liver is the gall bladder associated with?

Answer 1

The gall bladder is found on the visceral surface of the liver, and is associated with the Quadrate lobe.

Question 2

Explain the surface anatomy/ positioning of the gall bladder in relation to the MCL.

Answer 2

The fundus of the gall bladder is found in the Right- MCL inferior to the 9th costal cartilage.
Note that the fundus of the gall bladder is found lower than the anteroinferior border of the liver.

Question 3

What is the function of the gall bladder?

Answer 3

The gall bladder is a 50ml reservoir of bile

Question 4

What is the innervation of the gall bladder

Answer 4

Autonomic nervous system

Question 5

What is the blood supply of gall bladder?

Answer 5

Coeliac trunk 
Common hepatic artery 
Hepatic artery proper 
Right hepatic artery 
Cystic artery

Question 6

What is the venous drainage of the gall bladder?

Answer 6

Cystic vein

Portal vein

Question 7

True or false:

- Conjugated bilirubin is normally found in urine.

Answer 7

False

Question 8

True or false

- Bile contains digestive enzymes.

Answer 8

False

Question 9

What are substances stimulating bile secretion called?

Answer 9

Choloretics

Question 10

What are the contents of bile?

Answer 10

Bile salts
Bile pigment
Cholesterol
Steroid hormone

Question 11

What are the 2 main components in bile salt formation?

Answer 11

Cholesterol

Amino acids.

Question 12

Name 4 functions of bile acids:

Answer 12

1. Involved in digestion and absorption of fat.
2. Regulate their own synthesis from cholesterol, by hepatocytes
3. Function as choleretics (Substances stimulating bile secretion)
4. May increase colon motility/ laxative.

Question 13

Name the 2 primary bile acids (sterols synthesized from cholesterol):

Answer 13

1. Cholic Acid

2. Chenodeoxycholic acid.

Question 14

Name 2 secondary bile acids (conjugated amino acids):

Answer 14

Glycine

Taurine

Question 15

Primary bile acids are conjugated into secondary bile acids.
Use this to describe the formation of bile salts

Answer 15

Cholic acid and chenodeoxycholic acid are sterols synthesized by hepatocytes from cholesterol.
They are then conjugated into amino acids Glycine and Taurine to form soluble glycocholic acid and taurocholic acid.
Glycocholic acid and taurocholic acid are secreted and react with Na+ or K+ to produce bile salts.

Question 16

Name the 3 intermediates that bile salts must consist of:

Answer 16

Primary bile acids: cholic acid and Chenodeoxycholic acid
Secondary bile acids: Glycine and taurine
Na+ or K+

Question 17

Name 4 functions of bile acids

Answer 17

1. Increase colon motility/ laxative
2. Fat metabolism (Absorption and digestion of fat)
3. Regulate their own synthesis from cholesterol by hepatocytes
4. Function as choleretics.

Question 18

What portion of primary acids are converted into secondary bile acids but intestinal bacteria?

Answer 18

25%

Question 19

Name the 2 primary bile pigments and mention, what compound are they derivatives of?

Answer 19

Bilirubin
Billiverden
Both of which are a derivatives of haemoglobin

Question 20

What plasma protein is bilirubin bound to, in blood?

Answer 20

Albumin

Question 21

Name 2 other compounds that bile pigments are derived from:

Answer 21

Myoglobin

Cytochromes

Question 22

Name the carrier of bile pigments in the liver:

Answer 22

Glucuronic acid

Question 23

What is jaundice?

Answer 23

Jaundice is medical condition in which there is excessive bile production, ineffective bile excretion or obstruction of the bile duct leading to a build up bilirubin the body.
As a result, the skin, sclera and mucous membranes develop a yellow appearance

Question 24

What enzyme catalyzes conjugation within hepatocytes

Answer 24

Glucuronyl transferase

Question 25

What is the cause for neonatal jaundice?

Answer 25

There’s is impaired glucuronide formation due to transferase deficiency

Question 26

Which drug increases bile duct pressure?

Answer 26

Morphine

Question 27

Which drug stimulates glucuronyl transferase activity?

Answer 27

Phenobarb

Question 28

What is bilirubin broken down into in the intestines causing brown discoloration of faeces?

Answer 28

Stercobilin

Question 29

What is urobilin?

Answer 29

This is the remainder of the pigment that is reabsorbed and excreted by the kidneys

Question 30

What happens to bilirubin excretion in the case of hepatitis.

Answer 30

With hepatitis, excretion fails and jaundice results.

Question 31

Which duct connects the gall bladder to the common hepatic duct

Answer 31

The cystic duct.

Question 32

What epithelium in found lining the internal mucous membranes?

Answer 32

Simple columnar epithelium

Question 33

What is the main function of the gall bladder?

Answer 33

Store bile During inter digestive periods, the sphincter of Odi closes. Bile flows into a relaxed gall bladder Mucosa reabsorbs water and electrolytes rapidly

Question 34

What hormone stimulates gall bladder contraction?

Answer 34

Cholescystokinin

Question 35

What are the 2 mechanisms that control gall bladder contraction?

Answer 35

Neurological | Chemical

Question 36

Name the 2 mechanisms that control gall bladder contraction?

Answer 36

Neurological: - Stimulation of the vagus nerve causing the contraction of the gall bladder and relaxation of the sphincter Chemical: - when chyme reaches the upper small intestines, fatty acids and protein products stimulate the release of cholecystokinin Cholecystokinin is a hormone that stimulates the contraction of the gall bladder

Question 37

What are the main components of gallstones ?

Answer 37

Calcium. | Bilirubinate.

Question 38

How do gallstones form?

Answer 38

If Billirubin glucuronide is deconjugated, the free billirubin combines with calcium to form calcium bilirubinate which is highly insoluble.

Question 39

What is hepatic regeneration?

Answer 39

Ability of the liver to regenerate is highly effective.

Question 40

True or False: | - Conjugated bilirubin is normally found in urine.

Answer 40

False.

Question 41

True or False: | - Intrahepatic cholestasis is an indication for surgery.

Answer 41

True

Question 42

True or False: | - Gall-stones can cause extra-hepatic cholestasis.

Answer 42

True.

Question 43

True or False: | - Gilbert syndrome produces ↑ed conjugated bilirubin.

Answer 43

True

Question 44

True or False: | - Obstructive jaundice produces dark stools.

Answer 44

False.

Question 45

True or False | - Obstructive jaundice is always extra-hepatic.

Answer 45

False.

Question 46

True or False | - Obstructive jaundice may result in cholangitis.

Answer 46

True

Question 47

True or False | - Hemolysis results in ↑ed unconjugated bilirubin.

Answer 47

True.

Question 48

True or False - Hemolysis results in light stools • intra-hepatic cholestasis may be related to hepatitis T

Answer 48

False

Question 49

True or False | - Intra-hepatic cholestasis may be related to hepatitis.

Answer 49

True.

Question 50

True or False: | - Intra-hepatic cholestasis may be related to hepatitis.

Answer 50

True.

Question 51

What is the embryological derivative of the falciform ligament?

Answer 51

Remnants of the ventral mesogastrium

Question 52

What is the embryological derivative of the ligamentum teres hepatis/ round ligament?

Answer 52

Obliterated umbilical vein

Question 53

What is the embryological derivative of the ligamentum venosum

Answer 53

Ductus venosus

Question 54

Name, in order, the structures needle will pierce in a liver biopsy:

Answer 54

``` Skin. Fascia. Intercostal space. Diaphragm. Parietal peritoneum. Visceral peritoneum. Liver. ```

Question 55

Explain bile pigment formation:

Answer 55

``` In the macrophage: RBC death produces heme + globin+ iron Heme converted to biliverdin and Heme reduced to bilirubin Bilirubin is water insoluble Bilirubin binds to albumin which transports it to the liver ``` In the liver: Bilirubin + glucuronic acid is conjugated to bile salts by glucoronyl transferase to mono- or diglucuronide Which is transported via the biliary duct system through the duodenum Into the small intestines deconjugated by β glucuronidase And large intestines where bacterial oxidation occurs and it is excreted as stercobilinogen (in faeces) The rest of the 2-5% urobilinogen is re-absorbed via the blood stream into the kidney And then excreted as urobilin 20% into enterohepatic circulation

Question 56

What causes unconjugated bilirubinaemia?

Answer 56

Haemolysis Gilbert’s syndrome Criggler Najar Syndrome