Module 1 Unit 1: Bilirubin

Question 1

The liver is divided into 2 unequal lobes by the

Answer 1

Falciform ligament

Question 2

Functional units of the liver

Answer 2

Lobules/Acini

Question 3

Specialized epithelial cells located in lobules

Answer 3

Hepatocytes

Question 4

Liver lobules are centered around _____, which are interconnecting loose bands that contain branches of the PORTAL VEIN, HEPATIC ARTERY, and BILE DUCT

Answer 4

Porta triads

Question 5

Supplies the liver oxygen-rich blood

Answer 5

Hepatic artery

Question 6

Supplies the liver deoxygenated blood containing nutrients, drugs, and possibly microbes and toxins from GIT and spleen

Answer 6

Hepatic portal vein

Question 7

Capillary-like vessels lined by fenestrated endothelial cells

Answer 7

Sinusoids

Question 8

TRUE or FALSE: Lobules take up most of the oxygen, nutrients, and certain toxic substances.

Answer 8

False; Hepatocytes

Question 9

Small grooves between adjacent hepatocytes

Answer 9

Canaliculi

Question 10

Organ located posteriorly in the surface of the liver that stores and concentrates bile

Answer 10

Gallbladder

Question 11

Bile is a yellow-brownish liquid that has a pH of

Answer 11

7.6 - 8.6

Question 12

Carries bile from the liver to the gallbladder for storage

Answer 12

Bile duct

Question 13

Contain lysosomes with hydrolytic enzymes that can breakdown phagocytized worn-out blood cells, bacteria, and other foreign matter

Answer 13

Kupffer cells

Question 14

Secrete interleukins, tumor necrosis factor, collagenase, prostaglandins, and other factors involved in the inflammatory response

Answer 14

Kupffer cells

Question 15

Space between the endothelial lining of the sinusoids and the hepatocytes within a small cleft

Answer 15

Space of Disse

Question 16

Lie in the Space of Disse; synthesizes nitric oxide

Answer 16

Stellate/Ito cells

Question 17

Stellate cells transform into ______ when stimulated by injury

Answer 17

Collagen-forming cells

Question 18

Believed to be liver stem cells involved in the regeneration of hepatocytes and bile ducts after liver injury

Answer 18

Oval cells

Question 19

Major metabolite of heme

Answer 19

Bilirubin

Question 20

Normal daily production of bilirubin

Answer 20

250-350 mg

Question 21

85% of bilirubin is derived from the turnover of

Answer 21

Senescent RBCs

Question 22

15% of bilirubin is produced from ______ destroyed in the bone marrow and the catabolism of other heme-containing proteins

Answer 22

RBC precursors

Question 23

Senescent RBCs are destroyed in the spleen through phagocytosis by the

Answer 23

Reticuloendothelial cells (macrophages)

Question 24

Destruction of senescent RBCs release

Answer 24

Methemoglobin

Question 25

Methemoglobin splits into

Answer 25

Globin and Heme

Question 26

Oxidation of the porphyrin ring of heme by microsomal heme oxygenase produces ______ and releases _______

Answer 26

Biliverdin, Iron

Question 27

Biliverdin is reduced to bilirubin by _______ in the presence of NADPH

Answer 27

Biliverdin reductase

Question 28

Unconjugated bilirubin binds to a soluble carrier protein called

Answer 28

Ligandin or Y protein

Question 29

Ligandin transports unconjugated bilirubin to the

Answer 29

Smooth ER

Question 30

Enzyme used in the esterification of the propionic acid side chain of unconjugated bilirubin with glucuronic acid

Answer 30

Uridine diphosphate glucuronyl transferase (UDPGT)

Question 31

Refers to a group of 3 colorless tetrapyrroles compound

Answer 31

Urobilinogens

Question 32

Urobilinogens: 1. ______ 2. _______ 3. _______

Answer 32

1. Stercobilinogen 2. Mesobilinogen 3. Urobilinogen

Question 33

Oxidation product of Stercobilinogen

Answer 33

Stercobilin

Question 34

Oxidation product of Mesobilinogen

Answer 34

Mesobilin

Question 35

Oxidation product of Urobilinogen

Answer 35

Urobilin

Question 36

TRUE or FALSE: The oxidation products of urobilinogens are pigments that give the stool its orange-brown color.

Answer 36

True

Question 37

__% of urobilinogen is reabsorbed from the intestine and enters the enterohepatic circulation

Answer 37

20%

Question 38

2-5% of urobilinogen enters the circulation and appears in the _____

Answer 38

Urine

Question 39

Major fraction of glucuronides

Answer 39

Diglucuronide

Question 40

Minor fraction of glucuronides

Answer 40

Monoglucuronide

Question 41

Mechanism; substances absorbed in the GIT must pass through the liver first

Answer 41

First pass mechanism

Question 42

A polar and water-soluble compound that is found in the plasma in the free state

Answer 42

Conjugated bilirubin

Question 43

Half-life is less than 24 hours

Answer 43

Conjugated bilirubin

Question 44

Occurs in the cis form and reacts with diazo reagent WITHOUT an accelerator

Answer 44

Conjugated bilirubin

Question 45

Occurs in the trans form and reacts with diazo reagent WITH an acceleration

Answer 45

Unconjugated bilirubin

Question 46

Half-life is less than 12 hours

Answer 46

Unconjugated bilirubin

Question 47

CAN cross the blood-brain barrier

Answer 47

Unconjugated bilirubin

Question 48

A type of conjugated bilirubin covalently bound to albumin

Answer 48

Delta bilirubin

Question 49

TRUE or FALSE: Delta bilirubin can only be seen when there is a significant hepatic obstruction

Answer 49

True

Question 50

Half-life: 17-20 days

Answer 50

Delta bilirubin