lipids usually possess at least one of the following 3 structures, what are they?
fatty acid (acyl group)
what does each number in C16:1;9 represent?
C16 = number of Cs
1 = number of double bonds
9 = position of double bond
PUFAs not synthesized in significant amounts; made from the essential fatty acids
CONDITIONALLY essential fatty acids
3 conditionally essential fatty acids
GAMMA-LINOLEIC ACID "GLA"
ARACHIDONIC ACID "AA"
EICOSAPENTAENOIC ACID "EPA"
within the same omega series, a PUFA can be made ___ and with more ___ bonds (enzymes in the body to be discussed later)...but retains same ___ number
longer; double; omega
not synthesized by humans; in most vegetable oils: sunflower, safflower, evening primrose seed, corn, peanut, canola, olive
not synthesized by humans
in flaxseed oil
small amounts in some nuts, green leafy vegetables, canola, wheat germ, black currant seeds
sources of trans-fatty acids
partially hydrogenated margarine
commercial frying fat
high-fat baked goods
in trans Hs are on ___ ends of a double bond and in cis Hs are on ___ ends of a double bond
first, trans fatty acids are not essential and provide ___ ___ ___ to human health, whether from animals or plants.
second, while both saturated and trans fats increase levels of LDL, cholesterol, trans fats also lower levels of ___ cholesterol-increasing the risk of ___ ___ ___.
the NAS is concerned that dietary trans fatty acids are more ___ with respect to CHD than saturated fatty acids.
supported by a 2006 NEJM scientific review that states from a nutritional standpoint, the consumption of trans fatty acids results in considerable potential ___ but no apparent ___.
no known benefit
HDL; coronary heart disease
4 types of phospholipids
ether (as opposed to ester) linkage at first C of glycerol; account for ~10% of brain and muscle lipids
steroid lipids sub-divided into which 6 categories?
glucocorticoids: one important physiological function is the stimulation of ___ from ___. examples: ___ (hydrocortisone), corticosterone and ___ (synthetic)
gluconeogenesis; proteins; cortisol; dexamethasone
mineralocorticoids: enhance ___ retention and enhance excretion of ___, ___, and ___. the primary endogenous mineralocorticoid is ___.
Na+; K+,H+,NH4+; ALDOSTERONE
primarily produced by testes. e.g. testosterone and dihydrotestosterone (DHT). testes also make some 17 beta-estradiol (estrogen)
ergosterol (pro-D2 in yeast) and 7 dehydrocholesterol (pro-D3 in human skin) are examples of which type of steroid?
C24 steroids with functional groups -COOH and -SO3H. major ones in human bile are: cholic acid, deoxycholic acid, glycocholic acid and taurocholic acid
___ functional groups of bile acids dissociate to become negative ___ ...which bind to positive ions such as ___ or ___ to form bile ___
acidic; anions; K+; Na+; SALTS
complex of lipids (TG, phospholipids, cholesterol esters, free cholesterol) + protein (apolipoprotein, apoprotein, apo)
PL and Apo outside; TG, CE, and FC inside is characteristic of which structure?
structure of lipoprotein
lipids are composed (largely) of Cs and ___
together the C-H bond does not have ___
therefore, they do not form ___ bonds or ___ bonds
so...when lipids are added to water (solvent), they do not ___. they aggregate on top, forming ___ ___
mix; 2 layers
some lipids (e.g. phospholipids) possess O-, ___, or NH4+ at one end and ___ chain at the other
thus, these molecules exhibit both ___ and ___ properties
the hydrophilic ends interact with ___, the hydrophobic ends stay away and ___
results in the formation of ___ (hydrophobic ___ with hydrophilic ___)
PO4 3-; hydrocarbon; hydrophobic; hydrophilic; water; aggregate; micelles; core; surface
in rancidity, ___ bonds of acyl groups are oxidized by ___...accelerated by light and ___
DOUBLE; oxygen; temp.
2 examples of noxious/toxic substances produced via rancidity
malondialdehyde (toxic) and short-chain FAs
butter: bacteria produce short-chain FAs-->unpleasant odor
vegetable oils, whole grains, and cereals that have a high content of PUFAs are prone to ___. keep in air-tight, cool dark places
PARTIAL HYDROGENATION of oils can prevent ___ rancidity, but it causes production of ___ FAs, which increases cholesterol level and risk of ___ ___ ___
oxidative; trans; coronary heart disease
addition of ___ also can be added to help prevent against rancidity. examples are vit E, BHT (butyl hydroxytoulene), BHA (butyl hydroxyanisole)