Ch 21 - Lipids Of Physiologic Significance Flashcards
The _______ are heteregoneous group of compounds, including FATS, OILS, STEROIDS, WAXES amd related compounds, that are related more by their physical than by their chemical properties.
Lipids
Lipids have the common property of being _________ in water and _________ in nonpolar solvents such as ETHER, CHLOROFORM and BENZENE.
Insoluble
Soluble
Dietary supplementation with _______________ is believed to have beneficial effects in a number of chronic diseases, including cardiovascular disease, rheumatoid arthritis and dementia.
Long chain omega-3 fatty acids
Nonpolar lipids acts as _____________, allowing rapid propagation of depolarization waves along myelinated nerves.
Electrical insulator
Lipids are transported in the blood combined with proteins in _________________.
Lipoprotein practicles
_______________ include FATS and WAXES which are esters of fatty acids vith various alcohols.
Simple lipids
Esters of fatty acids with GYLCEROL.
Fats
______ are fats in the liquid state.
Oils
Esters of fatty acids with higher molecular weight monohydric alcohols.
Waxes
______________ are esters of fatty acids containing groups in addition to an alcohol and one or more fatty acids.
Complex lipids
Lipids containing in addition to fatty acids and an alcohol, a phosphoric acid residue. They frequently have nitrogen-containing bases (e.g choline).
Phospholipids
In many phospholipids the alcohol is GLYCEROL ______________ but in _________________ it is SPHINGOSINE, which contains an amino group.
Glycerophospholipids
Sphingophospholipids
Lipids containing a fatty acid, sphingosine and carbohydrate.
Glycolipids (Glycosphingolipids)
Because they are uncharged, acylglycerols (glycerides), cholesterol and cholesteryl esters are termed ____________.
Neutral lipids
_______________ are alipathic carboxylic acids.
Fatty acids
Fatty acids occur in the body mainly as ________ in natural fats and oils, but are found in the unesterified form as ______________, a transport form in the plasma.
Esters
Free fatty acids
True or False:
Fatty acids that occur in natural fats usually contain an even number of carbon atoms.
True
Containing one or more double bonds.
Unsaturated
Containing no double atoms
Saturated
The most frequently used systematic nomenclature names the fatty acid after the hydrocarbon with the same number and arrangement of carbon atoms, with -_____ being substitued for the final -e. (___________ system).
-oic
Genevan system
Saturated acids end in -_____ for example OCTANOIC ACID and unsaturated acids with double bonds end in -_______ for example OCTADECENOIC ACID.
- anoic
- enoic
Carbon atoms are numbered from the ___________________.
Carboxyl carbon (carbon no. 1)
The carbon atoms adjacent to the carboxyl carbon (nos. 2, 3, 4) are also known as the _______________ respectively.
Alpha, beta and gamma carbons
The terminal methyl carbon is known as the _____________.
w-or n-carbon
Major end product of carbohydrate fermentation by rumen organisms.
Acetic
In certain fats in small amounts (especially butter). An end product of carbohydrate fermentation by rumen organisms.
Butyric
Spermaceti, cinnamon, palm kernel, coconut oils, laurels and butter.
Lauric
Nutmeg, palm kernel, coconut oils, myrtles , butter
Myristic
Common in all animal and plant fats
Palmitic
18 Carbon atoms
Stearic
16 C atoms
Palmitic
14 C atoms
Myristic
12 C atoms
Lauric
6 C atoms
Caproic
5 C atoms
Valeric
4 C atoms
Butyric
2 C atoms
Acetic
Containg one double bond.
Monounsaturated
Containing two or more double bonds.
Polyunsaturated
These compounds, derived from eicosa (20-carbon) polyenoic fatty acids comprise the PROSTANOIDS, LEUKOTRIENES (LTs), and LIPOXINS (LXs).
Eicosanoids
______________ exist in virtually every mammalian tissue, acting as local hormones; they have important physiologic and pharmacologic activites.
Prostaglandins
They are synthesized in vivo by cyclization of the center of the carbon chain of 20-carbon (eicosanoic) polyunsaturated fatty acids to form a cyclopentane ring.
Prostaglandins
The _________________ have the cyclopentane ring interrupted with an oxygen atom (oxane ring).
Thromboxanes
The LEUKOTRIENES and LIPOXINS are a third group of eicosanoid derivatives formed via the ________________.
Lipoxygenase pathway
___________________ cause bronchoconstriction as well as being potent inflammatory agents, and play a part in asthma.
Leukotrienes
Most naturally occuring unsaturated fatty acids have ___________.
cis double bounds
The carbon chains of unsaturated fatty acids form a _____________ when extended at low temperatures.
Zigzag pattern
At higher temperatures, some bonds ________, causing chain shortening, which explains why biomembranes become thinner with increases in temperature.
Rotate
A type of _______________ occurs in unsaturated fatty acids, depending on the orientation of atoms or groups around the axes of double bonds, which do not allow rotation.
Geometric isomerism
If the acyl chains are on the SAME SIDE of the bond, it is -____ as in oleic acid; if on OPPOSITE SIDES, it is ______- as in elaidic acid.
Cis
Trans
Double bonds in naturally occuring unsaturated long-chain fatty acids are nearly all in the ____ configuration, the molecules being “bent” _____ degrees at the double bond.
Cis
120
Thus, oleic acid has a _______, whereas elaidic acid remains ____.
V shape
Straight
__________, with 4 cis double bonds, is bent into a U shape.
Arachidonic acid
True or False
DECREASE in the number of cis double bonds in a fatty acid leads to a variety of possible spatial configurations of the molecule.
False
INCREASE
____________ are presemt in certain foods, arising as a by-product of the saturation of fatty acids during hydrogenation or “hardening” of natural oils in the manufacture of margarine.
Trans fatty acids
True or False:
Physical and physiologic properties of fatty acids reflect CHAIN LENGTH and DEGREE OF UNSATURATION.
True
The melting points of even-numbered fatty acids _______ with chain length and _________ according to unsaturation.
Increase
Decrease
In nearly all fats
Palmitoleic
Possibly the most common fatty acid in natural fats; particularly high in olive oil
Oleic
Hydrogenated and ruminant fats
Elaidic
Corn, peanut, cottonseed, soy bean and many plant oils
Linoleic
Some plants, eg. oil of evening primrose, borage oil; minor fatty acid in animals
Gamma-linolenic