biocompounds that are soluble in organic solvents
lipids usually possess at least one of the following 3 structures, what are they?
fatty acid (acyl group)
fatty acids contain which functional group?
most abundant structural component of lipids
which type of acid is covalently bonded to alcohol?
what does the R in R-COOH represent?
R is hydrocarbon chain-minimum 3 carbons
type of fats primarily in animal fats
SAFA possess only ___ bonds b/t Cs
mono-unsaturated (MUFA) fatty acids possess ___ double-bond per molecule
3-C fatty acid
4-C fatty acid
16-C fatty acid
18-C fatty acid
20-C fatty acid
primarily in vegetable oils
poly-unsaturated (PUFA) fatty acids
poly-unsaturated fatty acids possess at least ___ double bonds b/t Cs
what are the 2 most commonly seen MUFAs in living tissue?
what does each number in C16:1;9 represent?
C16 = number of Cs
1 = number of double bonds
9 = position of double bond
3 alternate ways to annotate C16:1;9
cis-^-9 palmitoleic acid
3 alternate ways to annotate C18:1;9
cis-^-9 oleic acid
2 PUFAs that cannot be synthesized by the human body
LINOLEIC ACID "LA"
ALPHA-LINOLEIC ACID "ALA"
ratio associated with MUFAs
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"
C number where first double bond occurs (counted BACKWARD... the last C is C1)
Omega (w) number
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
what is C18:2;9,12?
linoleic acid (LA)
not synthesized by humans; in most vegetable oils: sunflower, safflower, evening primrose seed, corn, peanut, canola, olive
LA --> ___ --> DGLA --> ___
GLA; arachidonic acid
GLA - C18:3;6,9,12
most abundant PUFA in cell membranes
omega number of alpha-linoleic acid
not synthesized by humans
in flaxseed oil
small amounts in some nuts, green leafy vegetables, canola, wheat germ, black currant seeds
ALA --> ___ --> DHA
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
fat and oil
carotenoids, vit A, etc.
eicosanoids, licoprotein, etc.
___% of food lipids are triglycerides
fat: mainly from ___ sources (mostly SAFA)
oil: mainly from ___ sources (mostly PUFA)
all triglycerides contain fatty acids. fats and oils differ by the ___ ___ they have.
fatty acids differ by number of ___, position, ___, cis vs. trans of ___ bonds
Cs; number; double
exceptions to triglycerides
plant oils with little PUFA
plant oils with little PUFA include which 2 oils?
coconut and olive oils
high in medium-chain fatty acids C10-C14
high in OLEIC acid, a C18 MUFA C18:1,9
4 types of phospholipids
in cell membranes; body's reserve of PUFA
in addition to the 4 types of phospholipids, there are ___
ether (as opposed to ester) linkage at first C of glycerol; account for ~10% of brain and muscle lipids
vit A, E, K are all ___ lipids; they are all ___-soluble
beta-carotene, retinol examples of what?
2-methyl-1,3-butadiene is an example of what?
steroid lipids sub-divided into which 6 categories?
steroids which have -OH as primary functional group
CPPP is basic structure of which type of lipid?
a 27C sterol, implicated in the pathogenesis of atherosclerosis
when a cholesterol forms an ester with a FA, the ester is called a ___ ___
___ is the precursor of all other steroids
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
3 reproductive steroids
male sex steroids
female sex steroids
primarily produced by testes. e.g. testosterone and dihydrotestosterone (DHT). testes also make some 17 beta-estradiol (estrogen)
primarily produced by ovaries. e.g. 17 beta-estradiol and estrone
produced by corpus luteum and placenta. e.g. progesterone
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
vit D is from ___
sphingolipids are lipids that contain ___ as their alcohol component
2 examples of sphingolipids
sphingosine + FA + phosphocholine
sphingosine + FA + carbohydrate
3 examples of glycosphingolipids
compounds derived from lipids or mixtures containing lipids
3 examples of lipid derivatives
FAs and eicosanoids and lipoproteins
derived from 20C PUFAs
2 types of eicosanoids
3 types of prostanoids
regulate contraction & relaxation of smooth muscle
oppose platelet aggregation
stimulate platelet aggregation
from 20C PUFAs + glutathione
mediate allergic reaction
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
responsible for transport of lipids
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
formed by 2 layers of amphipathic molecules with hydrophobic tails facing each other
basic structure of all membranes; fluid mosaic model
breaking and mixing of dietary fat particles for further digestion by enzymes
emulsification usually done by ___ ___
which one is amphipathic? bile salt or dietary fat?
spoilage of lipid foods
in rancidity, ___ bonds of acyl groups are oxidized by ___...accelerated by light and ___
DOUBLE; oxygen; temp.
produces noxious/toxic substances
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)
double bonds in FAs of naturally occurring TGs are usually ___ form, which occupies more space
comparing 2 TGs with the same number of Cs
the one with the most double bonds (___) is ___ dense and appears as liquid at room temp.-->___
the more ___ one is ___ and appears as solid at room temp.-->___
unsaturated; LESS; OIL; SATURATED; DENSER; FAT