Question

• State the main digestive roles of the liver, pancreas, and gallbladder
• Identify three main features of liver histology that are critical to its function
• Discuss the composition and function of bile
• Identify the major types of enzymes and buffers present in pancreatic juice

Answer 1

1 liver helps in metabolism of proteins, carbohydrates and lipids.

liver produce bile, which are secreted into the small intestine contains bile pigments, bile salts , cholesterol, and phospholipids. bile helps in emulsification of fats.

pancreas during digestion produce pancreatic juice which contain enzymes like trypsinogen , chymotrypsinogen, procarboxypeptidases,amylases, lipases and nucleases. this enzymes get activated and helps in break down of starchs, sugars and fats.

gall bladder helps in concentration of the bile produced by the liver and also stores it in the gall bladder.

2- the hepatic parenchyma consist of hepatic lobules and is made up of liver cells called hepatocytes.

hepatocytes helps in production of bile.

central vein- vein present in the centre of hepatic lobules.

blood supply of liver parenchyma flows from portal triad into the sinusoids which opens into the central veins and empties into the hepatic vein

portal triad - each lobule is surrounded by portal triads which consist of three vessels- branch of hepatic artery, branch of portal vein and tributary of bile duct.

bile secreted by the hepatic cells are emptied into the bile canaliculus . from the canaliculus bile enters the tributary of bile duct.

3-bile contains bile pigments (bilirubin and biliverdin), bile salts cholesterol and phospholipids but no enzymes. function of bile is to emulsify fat ,i.e breaking down of fats into very small micelles.

4-pancreatic juice contains enzymes like trypsinogen, chymotrypsinogen, carboxypeptidases,amylases, lipases ,elatase and nucleases.

pancreatic juice is rich in sodium bicarbonates which buffers the acidic gastric juice in chyme.