Lipids Part 2 Flashcards
_______Lipids
Are bonded to other types of molecules
Complex
• Consist of a core of hydrophobic lipids surrounded by amphipathic proteins, phospholipids, and cholesterol
Lipoproteins
Composed of both lipids and proteins, called
apolipoproteins
T or F
• Larger LPP particles have larger core regions (contain relatively more TAG and cholesteryl ester)
True
T or F
The larger the LPP, the more lipid relative to CHON, therefore, lighter in density
True
Lipoproteins
Cassification
(based on ultracentrifugation)
- Chylomicrons [chylos]
- Very-low-density LPP [VLDL]
- Low-density LPP [LDL}
- High-density LPP [HDL]
80% - 90% triglycerides, 2% protein
Chylomicrons
55% - 65% triglycerides,
10% cholesterol,
5% - 10% protein
VLDL
10% triglycerides,
50% cholesterol,
25% protein
LDL
5% triglycerides,
20% cholesterol,
50% protein
HDL
• Location: surface of LPP particles
• Functions:
– Help maintain the structural integrity of LPP
– Serve as ligands for cell receptors
– Act as activators and inhibitors of the various enzymes that modify LPP particles
• Contain “Amphipathic helix”
Apolipoproteins
– Major protein on HDL
– Measure of anti-atherogenic HDL present in plasma
Apo A-I
– Is a large protein with MW 500 kD
– Principal protein on LDL, VLDL, and Chylomicrons
Apo B
Apo B 100 saaa?
LDL
VLDL
Apo B 48
Chylomicrons
Apo B-100
– Is found on…
– Ligand for the LDL receptor
LDL and VLDL
– Exclusively found in chylomicrons
Apo B-48
Apo E
– Found in (3)
– Serves as a ligand for the LDL receptor and the chylomicron remnant receptor
– Apo E2, Apo E3, Apo E4
LDL, VLDL, and HDL
Major lipoproteins
Chylomicrons
VLDL
LDL
HDL
Minor or abnormal lipoproteins
IDL
Lp (a)
Lp (x)
Beta VLDL
Chylomicrons
Account for the_____ of postprandial plasma
Readily float to the top of stored plasma and form a_____ layer – chylous, turbid, milky, cloudy, lipemic plasma/serum
Produced by the____
Deliver dietary (exogenous) lipids to…
turbidity
creamy
intestine
hepatic and peripheral cells
