the liver

• What is the importance of excretion in homeostasis?

  It removes toxic metabolic waste products
• What does the liver do in the excretion process?

  It breaks down harmful substances
• What are liver lobules composed of?

  Hepatocytes arranged in rows
• What connects each liver lobule to the hepatic vein?

  The central vein
• What is the function of Kupffer cells in the liver?

  They break down old red blood cells
• Why must excess amino acids be excreted?

  They contain damaging nitrogenous substances
• What is deamination in amino acid excretion?

  Removal of the amino group from amino acids
• What is formed after deamination of amino acids?

  Ammonia and organic acids
• How is ammonia converted to urea?

  By adding carbon dioxide in the ornithine cycle
• What are the main functions of the liver in excretion?

  • Breaks down harmful substances
  • Converts toxins into less harmful forms
  • Involved in detoxification of drugs and alcohol
  • Processes excess amino acids through deamination
• What is the significance of the liver's sinusoids?

  • Connect central vein to hepatic artery and portal vein
  • Contain Kupffer cells for breaking down red blood cells
  • Facilitate the exchange of substances in the liver