Lipids Flashcards
What are the 5 general functions of lipids?
1) Serve as hormones, 2) Aid in digestion, 3) Provide energy, storage, and metabolic fuels. 4) Functional/structural components 5) Insulation
What is the basic structure of cholesterol?
A steroid alcohol with 27 carbon atoms arranged in a tetrahedral sterane ring system
What are the two functions of cholesterol?
Organize cell membranes and control permebility
What is emulsification?
Solubilize cholesterol before absorption
What is esterification?
Hydrophobic molecule production
What is the ACAT site of action and function?
Intracellular catalyzes cholesterol esterfication
What is the LCAT site of action and function?
Externally catalyzes cholesterol esterification
What is the empirical formula of fatty acids?
R-COOH
What are the three sources of fatty acids?
Diet, Adipose tissue and biosynthesis
What are the four functions of fatty acids?
1) Produce energy via Beta-Oxidation 2) Produce phospholipids 3) Cell membrane maintenance 4) milk in females
What are the harmful effects of trans fatty acids?
1) Not able to (be recognized, thus) broken down my enzymes 2) More dense in membrane 3) Raises LDL/triglycerides 4) Lowers HDL 5) Cardiovascular Disease increase 6) Damage to Brain/nervous system
What is the Beta-oxidation process?
Shorten chain, acetyl CoA w/ oxalate = citrate
What is the structure of triglycerides?
3 fatty acids to a glycerol
What is the function of triglycerides?
Storage of fat in the tissues
How is triglyceride metabolized?
Digested in the duodenum and absorbed in the proximal ileum.
What are the phosphoglyceride functions?
1) Cell membrane 2) enzyme activators 3) metabolic fuels, 4) signaling molecules 5) Surfactant 6) component of lipoproteins
What are the functions of sphingolipids?
1) form major lipids of cel membranes 2) signaling in CNS
What are three fat soluble vitamins?
A, E and K
Draw the lipoprotein basic structure
After slide 82
What are the general functions of lipoproteins?
Hydrophilic adaptation to transport hydrophobic lipids to tissues/organs
What are the four functions of apolipoproteins?
1)Uptake/catabolism 2) Structural component, 3) cofactor to regulate enzymes 4) transfer of lipids between liproteins
Where do lipids fall on electrophoresis?
Top to bottom: Microns, LDL, VLDL, HDL
What is the most and least component of chylomicrons?
Triglycerides (86) and Cholesterol (5)
What is the main component of VLDL?
Triglycerides (55)
What is the main component of LDL?
Cholesterol (50)
What is the main component of IDL?
Cholesterol (36)
What is the main component of HDL?
Protein (50)
What are the apolipoproteins on chylomicrons?
A-I, E, B-48, C-I, C-II, C-III
What are the apolipoprotiens on LDL?
B-100
What is the function of A-I?
Structure, LCAT activator
What is the function of A-IV?
Activator LCAT and modulator of LPL
What is the function of B-48?
Structural, chylomicron secretion
What is the function of B-100
LDL!!!! receptor
What is the function of C-I?
Activator of LCAT, inhibitor of CETP, CRP, LDLR
What is the function of C-II?
Activator of LPL
What is the function of C-III?
Inhibitor of lipoprotein lipase
What is the function of E?
Uptake of micron remnant into IDL and to the liver
What is the purpose of the exogenous function?
Transport dietary lipids that are absorbed by intestine to liver/peripheral tissues,
What are the three pancreatic enzymes and their substances?
Lipase-triglycerides; Cholesterol esterase-cholesterol; Phospholipase A- phospholipids
Where are chylomicrons assembled?
Intentional epithelial cells
What is the importance of C-II?
Activates lipoprotein lipase causing hydrolysis of Fatty acids to be taken up by adipose/muscle cells
Where are fatty acids stored after triglyceride hydrolysis?
Stored as energy source/storage
How is the chylomicron remnant formed?
What remains after triglyceride hydrolysis
What is the important of apo-E?
required for endocytosis of the LIVER
What is the major carrier of exogenous lipids?
Chylomicrons
What is the major carrier of endogenous lipids?
VLDL
What is the purpose of the endogenous pathway?
Transfer hepatic device lipids to peripheral cells for energy metabolism