Lipids and Lipoproteins Flashcards
(13 cards)
What forms cholesterol?
Acetyl CoA
What is the critical step in the production of cholesterol?
Critical step is the production of mevalonate by HMG CoA reductase.
How is cholesterol transported?
Cholesterol is not soluble in plasma and is transported in lipoproteins.
Arrange the lipoproteins from smallest/most dense to largest/least dense.
HDL LDL IDL VLDL Chylomicrons
What do all lipoproteins contain?
TGs, cholesterol, cholesterol esters, phospholipids and apoproteins
State the function of HDL.
Reverses cholesterol transport
Protects against atherosclerosis
Carries 20-30% of TGs to liver
State the function of LDL.
Most atherogenic
Carries 60-70% of TGs.
Carries cholesterol to tissues
State the function of IDL.
Intermediated from LDL to VDL
State the function of VLDL.
Transports endogenous TAG to tissue.
Precursor to IDL and LDL
What is the function of chylomicrons?
Transport FA and cholesterol from diet to tissues
Describe how the exogenous lipid cycle occurs.
Dietary fat that is absorbed in the intestine is packaged into chylomicrons as TAGs.
Chylomicrons then circulate and deliver dietary TAGs throughout the body.
How are TAGS released from chylomicrons in the exogenous pathway?
TAGs are released by lipoprotein lipase (LPL)
Where is LPL found?
Found in capillaries of tissues within the body (most importantly within adipose)
