module 10- lipid synthesis Flashcards
(46 cards)
what is a precursor of storage lipids & membrane lipids
phosphatidate
how many stages is cholesterol synthesized from acetyl CoA in?
4
T or F: cholesterol synthesis is tightly regulated at several levels
T
what is a precursor of steroid hormones?
cholesterol
triacylglycerol vs phospholipid structure
T- 3 FA linked to glycerol backbone
P- 2 FA & 1 phosphate group linked to glycerol backbone
what is a common precursor for lipids
glycerol 3-P
how can glycerol 3-P derived
adipose tissue or DHAP
where does TAG vs phospholipid synthesis occur
TAG- liver & adipose tissue
P- all cells bc they are major component of membranes
phosphatidate
TAG & phospholipid precursor
triacylglycerol synthetase complex
ER membrane, catalyzes triacylglycerol synthesis from phosphatidate
T or F: CoA derivative of FA serves as activated substrate
T
where does triacylglycerol synthesis get used?
muscle or adipose tissue
phospholipids are ( ) molecules
amphiphilic- have both polar & non-polar region
where does phospholipid synthesis occur
ER
what must be linked to the phosphatidate for phospholipid synthesis
alcohol
how is CDP activated in yeast/bacteria?
linking diaclyglycerol to a CDP molecule
how is CDP activated in mammals?
alcohol is activated by linking it to CDP
what is the most abundant phospholipid
phsophotidylcholine
SAM
methyl donor for phospotidylcholine synthesis if choline is low
why is cholesterol important? (2)
1) critical component of cell membranes that ensures it has proper fluidity
2) precursor for steroid hormones- estrogen, progesterone, testosterone, cortisol, bile salts, vitaminD
T or F: all 27 carbons in cholesterol are derived from acetyl CoA
T
where does cholesterol synthesis occur?
cytosol & ER
2 characteristics of cholesterol
non-polar & insoluble in water
what does the 1st stage of cholesterol synthesis produce
mevalonate from 3 acetyl CoA
