Weekly Liver Histology and Physiology Exam - March 7, 2026 (Section A: MCQs) | MCQ Quiz | OmpathStudy Kenya

Question 1

What is the structural unit of the liver characterized by a hexagonal shape with a central vein in the middle?

Accepted Answer

Classical lobule — The classical lobule is hexagonal with a central vein at the center and portal triads at the periphery.

Question 2

Which structure defines the functional unit of the liver based on microcirculation and metabolic gradients?

Accepted Answer

Hepatic acinus — The acinus is the functional unit of the liver, defined by the blood supply from the terminal branches of the portal vein and hepatic artery.

Question 3

Which of the following is NOT a component of the portal triad?

Accepted Answer

Central vein — The portal triad consists of a bile duct, a branch of the hepatic artery, and a branch of the portal vein. The central vein is at the center of the lobule.

Question 4

Which zone of the hepatic acinus is most susceptible to ischemia/hypoxia?

Accepted Answer

Zone 3 — Zone 3 (centrilobular) is the furthest from the arterial blood supply and is the first to be affected by hypoxia and ischemia.

Question 5

Which zone of the liver acinus is the first to receive oxygenated blood from the hepatic artery?

Accepted Answer

Zone 1 — Zone 1 (periportal) is the closest to the blood supply and receives the best oxygenation.

Question 6

Phosphorus poisoning and eclampsia characteristically affect which area of the liver acinus first?

Accepted Answer

Zone 1 — Zone 1 (periportal) is specifically affected by phosphorus poisoning and eclampsia.

Question 7

The central vein of the hepatic lobule eventually drains into which vessel?

Accepted Answer

Hepatic vein — Central veins are tributaries that eventually merge to form the hepatic veins.

Question 8

In which zone does gluconeogenesis and oxidative metabolism primarily occur due to high oxygen availability?

Accepted Answer

Zone 1 — Zone 1 (periportal) has the highest oxygen tension and is the site of high metabolic activity like gluconeogenesis.

Question 9

Which cell type is responsible for the phagocytic activity within the liver sinusoids?

Accepted Answer

Kupffer cells — Kupffer cells are resident macrophages located within the liver sinusoids.

Question 10

The space of Disse is located between which two structures?

Accepted Answer

Sinusoidal endothelium and hepatocytes — The space of Disse (perisinusoidal space) lies between the sinusoidal endothelial cells and the hepatocytes.

Question 11

Which hepatic cells are primarily involved in Vitamin A storage and myofibroblast transformation during fibrosis?

Accepted Answer

Ito cells (Stellate cells) — Ito cells (Stellate cells) store Vitamin A and, when activated, contribute to liver fibrosis by producing collagen.

Question 12

Yellow fever and certain viral hepatitides frequently show maximal damage in which acinar zone?

Accepted Answer

Zone 2 — Zone 2 (midzonal) is classically associated with the necrosis seen in Yellow fever.

Question 13

A patient presents with toxic ingestion of Acetaminophen. Which zone of the liver is most likely to show necrosis?

Accepted Answer

Zone 3 — Acetaminophen toxicity causes centrilobular (Zone 3) necrosis because this zone contains the highest concentration of CYP450 enzymes.

Question 14

What type of capillaries are found in the liver?

Accepted Answer

Sinusoidal/Discontinuous — The liver contains sinusoidal (discontinuous) capillaries to allow for the exchange of large molecules between blood and hepatocytes.

Question 15

Bile flows in which direction relative to blood flow in the lobule?

Accepted Answer

Opposite direction (Centrifugal) — Blood flows from the portal triad toward the central vein (centripetal), while bile flows from the hepatocytes toward the portal triad (centrifugal).

Question 16

Which zone is least susceptible to viral hepatitis but most susceptible to metabolic toxins?

Accepted Answer

Zone 3 — Zone 3 is highly susceptible to metabolic toxins (like CCl4) and ischemia, but less so to primary viral insults compared to Zone 1.

Question 17

The portal triad is contained within a connective tissue sheath known as:

Accepted Answer

Glisson's capsule — Glisson's capsule is the connective tissue layer that covers the liver and extends into the portal tracts.

Question 18

Drug metabolism via the Cytochrome P450 system is most active in which zone?

Accepted Answer

Zone 3 — Zone 3 has the highest concentration of P450 enzymes, making it a hotspot for drug metabolism and metabolite-induced injury.

Question 19

Lymphatic fluid in the liver drains initially into which space before entering larger vessels?

Accepted Answer

Space of Mall — Fluid from the space of Disse flows into the space of Mall (at the edge of the portal canal) and then into lymphatic vessels.

Question 20

A liver biopsy shows necrosis specifically around the central vein. This is described as:

Accepted Answer

Centrilobular necrosis — Centrilobular necrosis refers to damage around the central vein, which corresponds to Zone 3.

Question 21

Congestive heart failure leads to 'Nutmeg Liver' primarily through damage to which area?

Accepted Answer

Zone 3 — Congestive heart failure causes hepatic venous congestion, affecting Zone 3 (the drainage area) most severely.

Question 22

Hepatocytes are derived from which embryological layer?

Accepted Answer

Endoderm — Hepatocytes and the biliary tree lining are derived from the endoderm of the foregut.

Question 23

In the context of the Portal Lobule model, what is at the center of the unit?

Accepted Answer

Portal triad — In the portal lobule model (focused on bile drainage), the portal triad is the center, and the boundaries are central veins.

Question 24

Which of the following is most likely to be high in Zone 1 hepatocytes?

Accepted Answer

Concentration of Glycogen — Zone 1 (periportal) is active in glycogen synthesis and gluconeogenesis.

Question 25

Bilirubin conjugation occurs within which part of the hepatocyte?

Accepted Answer

Smooth Endoplasmic Reticulum — The conjugation of bilirubin by the enzyme UDP-glucuronosyltransferase occurs in the Smooth ER.

Question 26

The apical surface of the hepatocyte forms the wall of which structure?

Accepted Answer

Bile canaliculus — The surfaces of adjacent hepatocytes form the bile canaliculi, representing the apical domain.

Question 27

What is the function of the Hering canal?

Accepted Answer

Connects canaliculi to bile ducts — The Canals of Hering act as a link between the bile canaliculi and the interlobular bile ducts in the portal triads.

Question 28

Alcoholic hepatitis usually results in injury to which zone first?

Accepted Answer

Zone 3 — Alcohol metabolism and its associated oxidative stress predominantly damage Zone 3.

Question 29

Which of the following describes 'Zone 2' of the hepatic acinus?

Accepted Answer

Intermediate area — Zone 2 is the midzonal region between the periportal (Zone 1) and centrilobular (Zone 3) areas.

Question 30

Which factor makes Zone 1 more resistant to ischemia compared to Zone 3?

Accepted Answer

Proximity to the hepatic artery — Zone 1 is closest to the hepatic artery, ensuring it receives the most oxygenated blood.

Question 31

Which protein is the most abundant produced by hepatocytes and released into the blood?

Accepted Answer

Albumin — Albumin is the major plasma protein synthesized by hepatocytes.

Question 32

What is the primary role of the basal surface (sinusoidal side) of a hepatocyte?

Accepted Answer

Absorption of nutrients and release of plasma proteins — The basal surface faces the space of Disse and is optimized for exchange between the blood and the cell.

Question 33

Kupffer cells are a specialized version of which cell line?

Accepted Answer

Monocytes/Macrophages — Kupffer cells are the resident tissue macrophages of the liver, originating from the monocyte lineage.

Question 34

Which of the following substances causes Zone 3 necrosis?

Accepted Answer

Carbon tetrachloride (CCl4) — Carbon tetrachloride is converted to free radicals in Zone 3 by P450, leading to necrosis.

Question 35

A biopsy reveals 'Councilman bodies.' These represent:

Accepted Answer

Apoptotic hepatocytes — Councilman bodies are eosinophilic, apoptotic hepatocytes often seen in yellow fever or viral hepatitis.

Question 36

Blood in the hepatic sinusoids is a mixture of blood from:

Accepted Answer

Hepatic artery and Portal vein — The sinusoids receive a mix of oxygen-rich arterial blood and nutrient-rich portal venous blood.

Question 37

Glucuronidation is a form of Phase II metabolism. Where is it most likely to happen?

Accepted Answer

Zone 3 — While Phase I and II occur throughout, Zone 3 is generally more active in drug metabolism processes.

Question 38

What happens to Stellate cells in chronic liver injury?

Accepted Answer

They lose Vitamin A and secrete collagen — Upon activation by injury, Stellate cells lose their Vitamin A droplets and transform into myofibroblasts that produce collagen, leading to fibrosis.

Question 39

The diameter of a liver sinusoid is maintained by which cells?

Accepted Answer

Stellate cells — Stellate cells have contractile properties that can help regulate the diameter of the sinusoids.

Question 40

What is the oxygen saturation of blood entering the liver via the portal vein?

Accepted Answer

Approximately 70-80% — Portal vein blood is partially deoxygenated (approx 75%) but carries 50-70% of the liver's total oxygen supply due to its high volume.

Question 41

Which enzyme localized in hepatocytes is used as a specific marker for liver injury?

Accepted Answer

Alanine Aminotransferase (ALT) — ALT is primarily found in hepatocytes and is a specific marker for liver cell damage.

Question 42

What structure separates the liver into right and left lobes anatomically on the surface?

Accepted Answer

Falciform ligament — The falciform ligament attaches the liver to the anterior abdominal wall and separates the right and left lobes.

Question 43

In the liver, where are stem cells (Oval cells) located?

Accepted Answer

Canals of Hering — Oval cells, which act as progenitor cells, are located in the Canals of Hering.

Question 44

Which of the following is synthesized by the liver to assist in fat emulsification?

Accepted Answer

Bile salts — Bile salts (derived from cholesterol) are synthesized by hepatocytes to emulsify fats in the intestine.

Question 45

Which condition is associated with 'bridge-like' fibrosis connecting portal tracts to central veins?

Accepted Answer

Cirrhosis — Cirrhosis is characterized by regenerating nodules surrounded by bands of fibrous tissue (bridging fibrosis).

Question 46

Which organelle is prominent in Zone 3 hepatocytes due to high lipid metabolism?

Accepted Answer

Smooth ER — Smooth ER is extensive in hepatocytes, especially in Zone 3, for detoxification and lipid metabolism.

Question 47

The 'Portal Lobule' concept emphasizes:

Accepted Answer

Exocrine function (bile) — The portal lobule model is designed to describe the exocrine function of the liver (bile drainage).

Question 48

Which zone is first affected by hemosiderin deposition in Hemochromatosis?

Accepted Answer

Zone 1 — In hereditary hemochromatosis, iron (hemosiderin) typically deposits in Zone 1 first.

Question 49

Which of the following is a function of Hepatocytes?

Accepted Answer

All of the above — Hepatocytes perform all these functions: synthesis of factors (II, VII, IX, X), glycogen storage, and the urea cycle.

Question 50

Where is the 'Space of Mall' located?

Accepted Answer

Between the portal canal connective tissue and the hepatocytes — The space of Mall is a small space at the boundary of the portal triad where lymph originates.

Weekly Liver Histology and Physiology Exam - March 7, 2026 (Section A: MCQs) | MCQ Quiz | OmpathStudy Kenya

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