| Term | Definition |
|---|
| Liver basic functions | metabolic regulation, hematological regulation and pile production |
| Metabolic regulation | 1. hepatocytes monitor and circulate levels of metabolites and adjust them (carbohydrates, lipids, blood glucose and amino acids); 2. excess nutrients are removed and stored (storage of iron reserves, glycogen and lipid reserves); 3. deficiencies are corrected by mobilizing stored reserves or performing appropriate synthetic activities (synthesis of somatomedins, synthesis and interconversion of nutrient types; and synthesis and release of cholesterol bound to transport proteins); 4. circulating toxins and metabolic waste products are removed for subsequent inactivation (inactivation of toxins), storage or excretion; 5. fat-soluble vitamins (ADKE) are absorbed and stored in the liver |
| Hepatocytes | liver cells; in a liver lobule form a series of irregular plates arranged like wheel spokes; plates are once cell thick; surfaces are covered with short microvilli; absorb and secrete materials into bloodstream across exposed surfaces |
| Blood circulation | blood leaves absorptive surfaces of digestive tract, enters hepatic portal system and flows into liver before reaching systemic circulation through hepatic veins |
| Hematological regulation | 1. Kupffer cells in live remove old or damaged RBCs, cellular debris and pathogens from the circulation; 2. liver cells synthesize plasma proteins, clotting factors and inactive hormone angiotensinogen that contribute to the osmotic concentration of blood, transport nutrients and establish clotting and complement systems |
| Liver receives | about 25% cardiac output; largest blood reservoir |
| Synthesis and secretion of bile | liver synthesizes bile, stores it in gallbladder and excretes it into lumen of duodenum; absorption and breakdown of circulating hormones (including insulin and epinephrine) and immunoglobulins; absorption and inactivation of lipid-soluble drugs |
| Bile | mostly water, some ions, bilirubin and bile salts |
| Bilirubin | pigment derived from hemoglobin |
| Bile salts | collective assortment of lipids; associate with lipids in chyme and make it possible for enzymes to break down lipids into fatty acids suitable for absorption |
| Water and ions | assist in dilution and buffering of acids in chyme as it enters the small intestine |
| Kupffer cells | phagocytic cells; engulf pathogens, cell debris, damaged blood cells and heavy metals like tin or mercury that are absorbed by digestive tract; found on sinusoidal lining, |
| Falciform ligament | anterior surface; ventral mesentery; marks division between left lobe and right lobe of the liver |
| Round ligament | thicker inferior margin of falciform ligament; marks path of degenerated fetal umbilical vein |
| Coronary ligament | suspends liver from inferior surface of the diaphragm |
| Anterior surface (Parietal surface) | follows smooth curve of the body wall |
| Posterior surface (Visceral surface) | has impressions of stomach, small intestine, right kidney and large intestine |
| Caudate lobe | small lobe next to right lobe separated by impression left by inferior vena cava |
| Quadrate lobe | inferior to caudate lobe, between left lobe and gallbladder |
| Liver segments | based on major subdivisions of hepatic artery, portal vein and hepatic ducts |
| Porta Hepatis | doorway to the liver; where afferent blood vessels and other structures converge to get blood to liver; they travel within CT of lesser omentum |
| Blood vessels that deliver blood to liver | hepatic artery proper and hepatic portal vein |
| Hepatic artery proper | one-third of blood is delivered to liver via this; supplies oxygenated blood |
| Hepatic portal vein | two-thirds of blood is delivered to liver via this; supplies nutrients and other chemicals absorbed from intestine |
| Hepatic veins | blood returns to systems via this; open into inferior vena cava |
| Liver lobules | basic functional units of liver divided by connective tissue; approximately 100,000 in each lobe |
| Central vein | what sinusoids between adjacent hepatocyte plates empty into; ultimately merges to form hepatic veins that empties into inferior vena cava |
| Sinusoids | have fenestrated walls that contain large openings that allow substances to pass out of the circulation and into spaces around hepatocytes |
| Sinusoidal lining | endothelial cells and Kupffer cells |
| Blood enters sinusoids through | small branches of portal vein and hepatic artery |
| Portal areas (hepatic triads) | six at each of the six corners of the lobule; contains 1. Branch of hepatic portal vein 2. Branch of the hepatic artery proper 3. Small branch of the bile duct |
| Bile canaliculi | narrow channels between opposing membranes of adjacent liver cells; extend outward through liver lobule away from central vein, connect with fine bile ductules |
| Bile ductules | connect with bile canaliculi; carry bile to a bile duct in the nearest portal area |
| Right and left hepatic ducts | collect bile from all of the bile ducts of the liver lobes; ducts unite to form common hepatic duct |
| Common hepatic duct | right and left hepatic ducts converge to form this; takes bile away from liver and will either 1. flow into common bile duct 2. enter cystic duct |
| Common bile duct | empties into the duodenum |
| Cystic duct | leads to gallbladder |
Combine with other sets
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