BMS 460 Lecture Notes - Critical Role, Stercobilin, Uridine Diphosphate
Document Summary
Absorption of dietary fats: bile and pancreatic lipase. Choleresis: liver cells secrete bile that contains bile salts, cholesterol, lecithin, bilirubin, electrolytes, and water. Colipase: amphipathic protein makes fat droplets covered with emulsifying agents accessible to water soluble lipase. Chylomicrons (triglycerides, phospholipids, cholesterol, apolipoproteins) carry fat from intestine to liver via general circulation. Micelles free molecules of fatty acids and monoglycerides. Droplets of triglyceride enclosed by membrane from the endoplasmic reticulum. Lipoproteins transport cholesterol and other lipids between tissues. Binding to lipoproteins to receptors is mediated through apoproteins, which are acquired as lipoproteins are assembled in enterocytes and hepatocytes. Mediates uptake of chylomicron remnants by the liver. Chylomicron: 80 1000 nm, 85% triglyceride, 5% cholesterol. Very-low-density lipoprotein (vldl): 30 80 nm, 55% triglyceride, 20% cholesterol. Intermediate-density lipoprotein (idl): 25 40 nm, 30% triglyceride, 40% cholesterol. Low-density lipoprotein (ldl): 15 20 nm, 5% triglyceride, 55% cholesterol, 20% protein. High-density lipoprotein (hdl): 5 10 nm, 5% triglyceride, 20% cholesterol, 50% protein.