Structure of the Liver

• What is the primary function of the liver in mammals?

  The liver is involved with the breakdown of toxic substances and the production of excretory waste.
• Why does the liver require a good blood supply?

  To carry out its roles of breaking down toxic substances and producing excretory waste.
• How is oxygenated blood supplied to the liver?

  Oxygenated blood is supplied to the liver via the hepatic artery.
• What is the role of the hepatic artery in the liver?

  The hepatic artery provides oxygen for aerobic respiration, fueling the metabolic activity of the liver cells.
• How does the liver receive blood from the digestive system?

  The liver receives blood from the digestive system via the hepatic portal vein.
• What is the function of the hepatic portal vein?

  The hepatic portal vein allows the liver to absorb and metabolize nutrients from the blood in the small intestine.
• What happens to deoxygenated blood after it exits the liver?

  Deoxygenated blood exits the liver in the hepatic vein and flows back to the heart.
• What is the role of the gallbladder in relation to the liver?

  The gallbladder stores bile and releases it into the duodenum via the bile duct.
• What components are found in bile?

  Bile contains bile salts for lipid digestion and bile pigments from the breakdown of hemoglobin.
• What are the main cell types in the liver?

  The liver is mainly made up of cells known as hepatocytes.
• How are hepatocytes organized within the liver?

  Hepatocytes are arranged into structures known as lobules.
• What supplies blood to each lobule in the liver?

  Each lobule is supplied with blood by branches of the hepatic artery and the hepatic portal vein.
• What are sinusoids in the liver?

  Sinusoids are wide capillaries within each lobule where blood from the hepatic artery and portal vein mixes.
• What occurs in the sinusoids of the liver?

  Blood within the sinusoids exchanges substances with nearby hepatocytes, allowing them to perform liver functions.
• What drains blood away from each lobule in the liver?

  Each lobule is connected to a branch of the hepatic vein that drains blood away from the lobule.
• What are the key structures and functions of the liver lobules?

  • Lobules are the functional units of the liver.
  • Each lobule receives blood from:
  • Hepatic artery (oxygenated blood)
  • Hepatic portal vein (nutrient-rich blood)
  • Blood mixes in sinusoids.
  • Hepatocytes perform liver functions.
  • Central vein drains blood into the hepatic vein.
• How do the functions of the hepatic artery and hepatic portal vein differ in the liver?

  The hepatic artery supplies oxygenated blood, while the hepatic portal vein supplies nutrient-rich blood from the digestive system.
• What should you be able to identify in liver tissue micrographs?

  • Liver lobules
  • Branches of the hepatic artery
  • Branches of the hepatic portal vein
  • Central vein
  • Sinusoids
• Liver Diagram

  A) Hepatic Vein (to heart)

  B) Liver

  C) Hepatic Artery (from heart)

  D) Stomach

  E) Bile Duct

  F) Pancreas

  G) Duodenum

  H) Hepatic Portal Vein

  I) Bile

  J) Gall Bladder

  
• Structure of Liver Lobule

  A) edge of lobule

  B) Branch of hepatic portal vein

  C) bile canaliculus

  D) branch of hepatic artery

  E) sinusoid

  F) hepatocyte

  G) endothelial cell

  H) central vein

  
• Liver Micrograph

  A) connective tissue separating lobules

  B) lobule

  C) central vein

  D) Hepatic Artery and Hepatic Portal Vein