Podcast
Questions and Answers
Where does the blood from the portal vein pass through before entering the systemic circulation?
Where does the blood from the portal vein pass through before entering the systemic circulation?
Which organ receives the breakdown products of hemoglobin carried by blood from the spleen?
Which organ receives the breakdown products of hemoglobin carried by blood from the spleen?
What is the primary organ in which aged erythrocytes are removed from the blood?
What is the primary organ in which aged erythrocytes are removed from the blood?
Which vessels empty into hepatic sinusoids in the liver?
Which vessels empty into hepatic sinusoids in the liver?
Signup and view all the answers
What is the arrangement in the liver called where a set of sinusoids are present between veins?
What is the arrangement in the liver called where a set of sinusoids are present between veins?
Signup and view all the answers
Which cell type in the liver is known for accumulating lipids?
Which cell type in the liver is known for accumulating lipids?
Signup and view all the answers
What is the name of the connective tissue capsule that invests the liver?
What is the name of the connective tissue capsule that invests the liver?
Signup and view all the answers
Which cells in the liver are characterized by a spoke-like arrangement around a central vein?
Which cells in the liver are characterized by a spoke-like arrangement around a central vein?
Signup and view all the answers
What is the basis of the classic hepatic lobule structure in the liver?
What is the basis of the classic hepatic lobule structure in the liver?
Signup and view all the answers
What defines the boundaries of a hepatic lobule in the liver?
What defines the boundaries of a hepatic lobule in the liver?
Signup and view all the answers
Study Notes
Liver Introduction and Function
- The liver is the largest gland in the body, weighing approximately 1.4 kg.
- It receives all materials absorbed by the gastrointestinal tract except some lipids, which are carried by lymphatics to enter the general circulation.
- Blood from the portal vein, which drains the entire gastrointestinal tract and spleen, passes through the liver before entering the systemic circulation.
Blood Supply and Hepatic Portal System
- The liver has a dual blood supply, with both venous (portal) and arterial (hepatic) bloods percolating through the liver sinusoids and exiting by way of the hepatic vein.
- The hepatic portal system is a unique arrangement of sinusoids between veins that enables the liver to filter blood from the gastrointestinal tract.
Histology
- The liver is surrounded by a delicate connective tissue capsule called Glisson's capsule.
- The parenchyma of the liver consists of large polyhedral epithelial cells, hepatocytes, arranged in plates that radiate from the central vein.
- Hepatocytes are separated by blood sinusoids and have surfaces that bear numerous well-developed microvilli.
- The plates of hepatocytes are supported by a delicate stroma consisting primarily of reticular fibers.
Hepatic Lobule
- The classic hepatic lobule is a hexagonal unit consisting of a central vein, portal areas, and plates of hepatocytes.
- Each lobule contains a portal triad, which consists of a branch of the portal vein, a branch of the hepatic artery, and an interlobular bile duct.
- The liver consists of approximately one million hepatic lobules.
Bile Production and Secretion
- Bile is produced by hepatocytes and poured into bile canaliculi, which are spaces between the plasma membrane of adjacent cells.
- Bile canaliculi become continuous with intralobular ductules, which in turn become continuous with interlobular ducts at the portal triad.
Other Cells and Structures
- Hepatic macrophages (Kupffer cells) are actively phagocytic cells that form part of the sinusoidal lining.
- Lipocytes are cells that accumulate lipid and are most numerous in the peripheral and intermediate zones of the hepatic lobule.
- The liver acinus is a smaller unit of liver structure defined by the hepatic tissue supplied by a terminal branch of the hepatic artery and portal vein and drained by a terminal branch of the bile duct.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Learn about the function and anatomy of the liver, the largest gland in the body. Understand how blood from the portal vein passes through the liver before entering the systemic circulation.
