University:
York University
Course:
BIOL 2020 | Biochemistry
Academic year:

2023
Views:

127

Pages:

2
Author:

Nick T.

Lipoproteins Chalomicrons tronspert lipids from the diet Lowest density Very Lasily (VLDS 'Corry triglycerides cholesterol from liver to peripheral tissues Intermediate-Do (IDL) Carry peripheral Use in remnets of VLDLS From tissue Synthesis back to liver for Bad Low Density Liposestins (LDL) Transport mostly liver te Cell Cholesterol from the peripheral tissues membranes where it is used in or for sitriod hormone Synth Good High Deotits Lapapsatser (HPL) Transport Chelestored from dead or dying Cells is Converted to bile acids bach de liver where it "Bile acids excreted used for digestion Good and Bad Cholesterol Do High concentrations of cholesterol circulating in blood correlate with heart disease (coronary artery blockage) Since HDLs are used to remove cholesterol and LDLs are used to deliver cholesterol: -HDLs are called "Good" cholesterol -LDLs are caled "Bad" cholesterol Cholesterol in blood is determined by measuring LDL and HDL concentrations Recent research indicated that the ratio of LDL/HOL may be more important than total cholesterol in predicting risk of heart disease Lipid Metabolism Metabolism of Triglycerides Triglycerides undergo: Hystrolvata to fatty acids and glycerol Fatty acide undergo: -Re-synshes into friglycerides for storage Conversion to acetyl SCOA by the fi-Oxidation Pathway Storage and Mobilization of Triglyceri After a meal, blood glucose levels are high High levels of insulin and low levels of glucagon -Insulin activates the synthesis of triglycerides for storage When blood glucose levels are low. Insulin levels drop and glucagon levels rise Glucagon activates an enzyme that hydrolyzes triglycerides to release free fatty acids into the blood to be oxidized for energy Storage and Mobilization of Triglyceride... Fat is stored in special fat storage cells called adipocytes Triglycerides must bo disassembled to cross membranes Fatty acids and glycerol aru en regasembled into new then triglycorides Fat is continually disassembled and reasoembled