Topic D.3:  Functions of the Liver

Essential Idea:  The chemical composition of the blood is regulated by the liver.
At SHS, Topic D.3 is taught in the following class unit(s):

Statements & Objectives:

D.3.U1  The liver removes toxins from the blood and detoxifies them.
  • Define “detoxification” as related to liver function.
  • Explain the role of the liver in the detoxification of alcohol (including role of ethanol dehydrogenase).
  • Outline the role of the liver in the detoxification of ammonia (and formation of urea).
D.3.U2  Components of red blood cells are recycled by the liver.
  • State the length of a typical red blood cell life span.
D.3.U3  The breakdown of erythrocytes starts with phagocytosis of red blood cells by Kupffer cells.
  • Explain how the structure of Kupffer cells fits their endosymbiosis function.
  • Create a flowchart to illustrate the steps and products of the splitting of hemoglobin
D.4.U4  Iron is carried to the bone marrow to produce hemoglobin in new red blood cells.
  • Explain how and why iron is transported to the bone marrow bound to transferrin.
  • List three anatomical structures that have transferrin receptors on their cell membranes.
  • Outline the storage of iron in the liver and spleen (including the role of ferritin).
D.3.U5  Surplus cholesterol is converted to bile salts.
  • Outline the roles of hepatocytes in the conversion of excess cholesterol into a component of bile.
  • Explain the synthesis of VLDL cholesterol by hepatocytes for transport of triglycerides.
  • Describe how the amount of saturated fat in a diet affects the amount of VLDL cholesterol synthesis by the liver.
D.3.U6  Endoplasmic reticulum and Golgi apparatus in hepatocytes produce plasma proteins.
  • Define and list examples of “plasma proteins.”
  • Explain why hepatocytes have a lot of RER and Golgi.
D.3.U7  The liver intercepts blood from the gut to regulate nutrient levels.
  • Explain the storage and release of glucose (including the role of glycogen, insulin and glucagon).
  • Outline the role of the liver in protein metabolism (and resulting nitrogenous waste formation).
D.3.U8  Some nutrients in excess can be stored in the liver.
  • List four example nutrients that can be stored by the liver.
D.3.A1  Causes and consequences of jaundice.
  • Outline the function and source of bilirubin.
  • Explain the role of hepatocytes and glucuronic acid in the conversion of bilirubin.
  • List components of bile.
  • Outline the role of bile ducts and gall bladder in the transport and storage of bile.
  • Describe when, where and why bile is secreted during digestion.
  • Define and list causes and symptoms of jaundice.
  • Describe the use of UV light as a treatment for jaundice.
D.3.A2  Dual blood supply to the liver and differences between sinusoids and capillaries.
  • Draw and label a diagram of the liver, including the left and right lobes, hepatic portal vein, hepatic artery and the hepatic vein.
  • Compare liver blood supplies in terms of blood source (arrives from…), blood destination (flows towards…), and relative oxygen concentration.
  • Draw a labeled diagram of a sinusoid, inclusive of:  bile canal cells, bile duct, hepatocytes, Kupffer cells, arterioles and venules.
  • Compare sinusoids to capillaries.
  • Outline the relationship between liver lobes, lobules and sinusoids.
D.3.NOS  Educating the public on scientific claims—scientific studies have shown that high-density lipoprotein could be considered “good” cholesterol.
  • Compare and define LDL, HDL, IDL, VLDL and chylomicrons.
  • Explain the structure of lipoproteins, including the types of molecules found in the hydrophobic core and hydrophilic surface.
"When we try to pick out anything by itself, we find it hitched to everything else in the Universe." 
 John Muir,   1911