Hepatic Physiology

Question 1

The basic functional unit of the liver is the ________

Answer 1

Liver Lobule

Question 2

The liver lobule is constructed around a _____, which empties into the ______

Answer 2

Central Vein; Hepatic Vein

Question 3

The liver can be compared to being the “_________” center of the body

Answer 3

waste management

Question 4

The lobules are composed of many ______, which are collections of ______ that radiate out from the central vein like spokes of a wheel

Answer 4

Cellular Plates; Hepatocytes

Question 5

Adjacent to the hepatocytes are _______ that collect bile secreted by the hepatocytes and empty into Bile Ducts

Answer 5

Bile Canaliculi

Question 6

What are small branches of the portal vein called? Where do they transport blood from?

Answer 6

Portal Venules; Transport venous blood coming in from the gastrointestinal system

Question 7

Trace the path of blood from GI system to the IVC through the liver

Answer 7

GI > Hepatic portal vein > Portal Venules > Hepatic sinusoids > Central Vein > Hepatic Vein > IVC

Question 8

Where hepatic arterioles supply blood to?

Answer 8

providing oxygenated blood to the lobule

Question 9

The sinusoids are lined by endothelial cells and large ______

Answer 9

Kupffer Cells (gate keeper cells)

Question 10

The spaces between the lining of the sinusoid and the cellular plate are called the _________

Answer 10

Spaces of Disse (AKA perisinusoidal spaces)

Question 11

What do Kupffer cells do?

Answer 11

Kupffer Cells are resident macrophages that line the sinusoid and are capable of rapidly phagocytizing bacteria and other foreign invaders

Question 12

What % of bacteria entering circulation from the intestine makes it past the Kupffer army and into systemic circulation?

Answer 12

Less than 1%

Question 13

The portal vein runs _____ the liver while the hepatic veins _____ the liver

Answer 13

Enters, exits

Question 14

The Hepatic Portal systems’ main function is to

Answer 14

drain blood from the GI tract and takes blood to the liver for further absorption and processing of material.

Question 15

Trace the path of oxygenated blood from the aorta to the liver lobules

Answer 15

Abdominal Aorta > Celiac trunk > Hepatic Artery > right and left hepatic arteries > hepatic arterioles > liver lobules

Question 16

Function of the hepatic vein

Answer 16

Draining deoxygenated venous blood and cleansed portal blood from the liver.

Question 17

All central veins drain into the ____

Answer 17

Hepatic vein

Question 18

Most common cause of portal hypertension

Answer 18

Cirrhosis of the liver: damage to the liver to which the architecture (hepatocytes) of the liver is lost and disrupts the flow of blood through the portal vein.

Question 19

Portal hypertension is characterizes as an ______ in Portal Vein

Answer 19

Increase in intravascular pressure

Question 20

Portal hypertension can result in

Answer 20

(ASCE)
Ascites
Splenic Engorgement
Caput Medusae: recanalization of the paraumbilical veins
Esophageal Varices: Dilated submucosal veins in the lower third of the esophagus

Question 21

Liver functions in carbohydrate metabolism (3 things)

Answer 21

Storage of large amounts of glycogen (chains of glucose)
Conversion of galactose and fructose to glucose
Gluconeogenesis (making glucose from fats or proteins)

Question 22

The liver plays an especially important role in maintaining a normal blood _____ concentration

Answer 22

glucose

Question 23

An excess of blood glucose triggers _____ within the liver

Answer 23

Glycogenesis

Question 24

The breakdown of glycogen into glucose is called

Answer 24

Glycogenolysis

Question 25

If both blood glucose and liver glycogen stores are low, what process must occur?

Answer 25

Gluconeogenesis: conversion of certain amino acids or glycerol from triglycerides into glucose.

Question 26

What functions does the liver have in fat metabolism?

Answer 26

Oxidation of fatty acids Synthesis of cholesterol, phospholipids, and most lipoproteins Synthesis of fats from proteins and carbohydrates

Question 27

Fats initially bypass the liver by _____

Answer 27

Lymphatic drainage (via chylomicrons)

Question 28

______ hydrolyzes triglycerides

Answer 28

Lipoprotein Lipase

Question 29

By what process can the liver can split free fatty acids into compounds that form Acetyl Coenzyme A (Acetyl-CoA).

Answer 29

Beta-Oxidation

Question 30

________ is the process by which excess proteins or carbohydrates are synthesized into fat for storage in adipose tissue

Answer 30

Lipogenesis

Question 31

____ and ____ are synthesized by the hepatocytes

Answer 31

Bile and phospholipids

Question 32

In order for the absorbed amino acids to be used for energy or converted into fats or carbohydrates, this process must occur

Answer 32

Deamination: This is when an amine group is removed from an amino acid, creating Ammonia (NH3).

Question 33

Hepatic Encephalopathy in liver disease can be caused by high levels of

Answer 33

Ammonia

Question 34

_______ is the process that creates Ammonia

Answer 34

Deamination

Question 35

To get rid of Ammonia, the liver must convert it to _____ to be excreted in the kidneys

Answer 35

Urea (via urea cycle)

Question 36

hypoalbuminemia can occur in liver failure and results in

Answer 36

Edema and contribute to ascites

Question 37

Main plasma protein synthesized by the liver

Answer 37

Albumin (Additionally thrombopoietin and angiotensinogen)

Question 38

The so-called Non-Essential amino acids can all be synthesized by the liver through a process called _____

Answer 38

Transamination

Question 39

Important markers (transaminase enzymes) for liver injury

Answer 39

Alanine Transaminase (ALT) Aspartate Transaminase (AST)

Question 40

The vitamin stored in the greatest quantity in the liver is ______

Answer 40

Vitamin A

Question 41

Apoferritin is a universal intracellular protein in hepatocytes that has the ability to store ____

Answer 41

Iron

Question 42

Serum _____ lab test can be used in the diagnosis of iron deficiency anemia

Answer 42

Ferritin

Question 43

T/F - coagulation factors and other proteins necessary for coagulation and hemostasis are made in the liver

Answer 43

True

Question 44

Which coagulation factors are produced by Vitamin K?

Answer 44

Factors II, VII, IX, and X

Question 45

We obtain Vitamin K from dietary intake of _____

Answer 45

green, leafy vegetables.

Question 46

Whether due to Vitamin K deficiency, liver disease, or both, these two things occur

Answer 46

Increased risk of hemorrhage Prevents effective hemostasis

Question 47

In patients with severe liver disease, thyroxine and steroid hormones can accumulate in large emounts, potentially causing ____ in men

Answer 47

Gynecomastia

Question 48

A large percentage of prescribed pharmacologic drugs are metabolized in the liver by _____

Answer 48

Cytochrome P450 enzymes.

Question 49

Bilirubin is an end product of what process

Answer 49

hemoglobin degradation

Question 50

Lifespan of redblood cells

Answer 50

120 days

Question 51

Path of RBCs to Bilirubin

Answer 51

Fragile RBCs rupture in circulation > free hemoglobin taken up by tissue macrophages > heme oxygenase converts heme to biliverdin > reduction of biliverdin to unconjugated bilirubin > conjugated in liver to become bilirubin

Question 52

How is unconjugated bilirubin taken up by the hepatocytes?

Answer 52

Quickly binds with albumin and is taken up by Hepatocytes via Facilitated Diffusion

Question 53

Conjugated Bilirubin is excreted by _____ Transport into the Bile

Answer 53

Active Transport

Question 54

______ in the intestine converts about half of Bilirubin into Urobilinogen

Answer 54

Bacterial action

Question 55

T/F - a large portion of Urobilinogen is reabsorbed into the Hepatic Portal System

Answer 55

T

Question 56

Jaundice occurs as a result of accumulation of large quantities of _____ in the extracellular fluids because of high blood levels and can be ___ or ____

Answer 56

Bilirubin; conjugated or unconjugated

Question 57

Two types of Jaundice

Answer 57

Hemolytic anemias result in rapid release of bilirubin into the blood. Liver disease or a downstream hepatobiliary obstruction can result in the inability to excrete even a normal amount of bilirubin

Question 58

What is "direct" bilirubin? "indirect"?

Answer 58

Direct: conjugated Indirect: Unconjugated

Question 59

Hemolytic jaundice results in large amounts of serum _____ bilirubin

Answer 59

unconjugated

Question 60

liver disease and obstructive jaundice result in high levels of serum _____ bilirubin

Answer 60

conjugated

Question 61

These cells line the sinusoid and phagocytize bacteria and other foreign invaders in the liver

Answer 61

Kupffer Cells

Question 62

Ascites is a result of _____ (portal HTN) and ______ (low serum albumin from liver disease)

Answer 62

Increased hydrostatic pressure; decreased oncotic pressure