lipid metabolism Flashcards
fatty acids
long carboxylic acids
TAGs
3 FA on glycerol backbone via esterification bond
cholestrol
4 ring structure and precursor of steroids
stabilizes membrane
how does choleterol contribute to the plasma membrane at LOW temperatures
increases fluidity
how does cholestrol contribute to the plasma membrane at high temps?
increase rigidity/ reduces fluidity
eocosinoids
derived from arachadonic acid and function as prostaglandins to modulate inflammation
sphingomylein
Sphingomyelin is composed of a sphingosine, a fatty acyl group and a phosphorylcholine head group (41). Its overall structure is roughly equivalent to replacing glycerol and a fatty acyl group in glycerophospholipid with sphingosine.
saturated fatty acids
c-c bonds only
structure of prostaglandins
unsaturated fatty acids with a cyclopentane and derived from arachadonic acid
unsaturated fatty acids
at least one c=c bond present
Z fatty acids
cis
E fatty acids
trans
omega notion for fatty acids
non-carbonyl end
omega notion for fatty acids
non-carbonyl end
which orientation do fatty acid unstaruated bonds prefer to orient
cis –> introduces unique bending of the FA chains and prevents proper stacking
do unsaturated fatty acids have higher or lower melting points/boiling points
lower boiling point because of chain bending (cis bonds)
do unsaturated fatty acids make the plasma membrane more or less fluid
more fluid
hydrogenation of unsaturated fats
convert from unsaturated to saturated which produces trans fat
trans fat is more likey to exsist in what phase at room temp?
solid because of tight packing and lack of cis double bonds
what are lipids packaged into in the small intestine
chylomicrons
chylomicron structure
largely fats, apoproteins, cholesterol, phospholipids
where are chylomicrons released
lacteals which release them into the lymphatic system
where are left over chylomicrons recycled
liver
VLDL
liver produces very low density lipoproteins and also deliver FA to tissue
chylomicron function
deliver lipids to cells and tissue in body
why are LDLs different from VLDLs and chylomicrons
VLDLs and chylomicrons primarily transport fatty acids to tissue, LDLs transport cholesterol
HDL
transport cholesterol and other lipids away from tissue for processing and secretion
what is cholesterol returned to the liver converted into
bile
adipocytes
fat cells that are primary storage of lipids
what metabolic activities involving lipids do epinephrine and glucagon trigger?
hydrolysis of TAGs via hormone sensitive lipase