liver

• liver is the largest gland in the body
• liver weighs about 1.4kg
• liver has 2 lobes the _ lobe is slightly larger


  right
• gall bladder is connected to the liver via the hepatic ducts
• gall bladder stores bile produced by the

  liver
• gall bladder contracts to release bile into the duodenum through the 


  bile duct
• liver receives oxygenated blood through the

  hepatic artery
• liver receives nutrients through the GI tract through the

  hepatic portal vein
• blood leaves the liver and goes back to the heart through the hepatic vein and then the 


  inferior vena cava
• liver lobule is major functional subunit of the liver and is _ in shape 


  hexagonal
• liver lobule

  labels

  A) hepatic portal vein

  B) hepatic artery

  C) bile duct

  D) central vein

  E) hepatocyte

  F) sinusoids

  
• portal triad is made up of

  • branch of hepatic portal vein
  • branch of hepatic artery
  • bile duct
• sinusoids are channels that are lined with hepatocytes, where blood from the hepatic artery and hepatic portal vein mix
• hepatocytes function 


  make bile
• Kupffer cells are fixed phagocytes that phagocytose 


  old blood cells and any bacteria
• Kupffer cells are immune cells, they come from

  bone marrow (bone monocytes) and migrate to the liver
• bile canaliculi run through hepatocytes and carry bile from hepatocytes to the bile duct
• bile is stored in the

  gall bladder
• liver produces around 0.8-1L of bile per day
• bile has yellow-green consistency
• bile is alkali
• bile salts are based on the structure of cholesterol
• bile salts emulsify fats
• emulsifying fats means that 


  pancreatic lipase can work more easily, and lipids can be absorbed ore easily
• bile pigments function


  in excretion
• bile salts function 


  digestion
• bile pigments break down haem to recycle iron
• bilirubin is yellow and is the breakdown product of haem
• bilirubin is metabolised by bacteria to give stercobilin (which is brown)
• liver function

  • phagocytosis
  • synthesis of bile salts
  • excretion of haem
  • processing drugs and hormones
  • activating vitamin D
  • storage e.g. glycogen and vitamin A (as retinol)
  • metabolism of carbohydrates, lipids and proteins
• liver is in absorptive state during glycogenesis which is when 


  glucose is converted to glycogen (stimulated by insulin)
• genesis means 


  to generate
• liver is in post-absorptive state when plasma glucose levels are low
• adrenaline is released from the adrenal gland and glucagon from alpha islet of Langerhans cells, which stimulate the liver into converting 


  glycogen into glucose
• glycogenolysis is the process of 


  glycogen turning to glucose
• gluconeogenesis is 


  generating new glucose
• gluconeogenesis is generating glucose from non carbohydrate sources
• when glycogen levels are low, glucose can be formed from

  lactic acid, amino acids, glycerol derived triglycerides
• 3 carbon chains can be used in

  gluconeogenesis
• in the absorptive state glycogen is formed from glucose by the pancreas known as 


  glycogenesis