LIPIDS Flashcards
________ an organic compound found in living organisms that is insoluble (or only sparingly soluble) in water but soluble in nonpolar organic solvents
LIPID
What are the two common methods for sub classifying lipids?
BIOCHEMICAL FUNCTION AND SAPONIFICATION REACTION
What are the 5 categories of lipids based on biochemical function?
(EMEMP) [ENERGY-STORAGE LIPIDS, MEMBRANE LIPIDS, EMULSIFICATION LIPIDS, MESSENGER LIPIDS, PROTECTIVE COATING LIPIDS]
2 Categories of lipids based on saponification
[SAPONIFIABLE AND NON SAPONIFIABLE]
Energy storage lipids
(T) [triacylglycerol]
Membrane lipids
(PSC) Phospholipids, sphingoglycolipids, cholesterol
Emulsification Lipids
(B) [bile acids]
Messenger Lipids
(SE) [steroid hormones and eicosanoids]
Protective- Coating Lipids
(B) [biological waxes]
Saponifiable Lipids
(TPSB) [triacylglycerol, phospholipids, sphingoglycolipids, biological waxes]
Nonsaponifiable Lipids
(CSBE) [cholesterol, steroid hormones, bile acids, eicosanoids]
___________ is the hydrolysis reaction that occurs in basic solution is called?
Saponification
Lipids that are converted into smaller molecules when hydrolysis occurs ____________
Saponifiable lipids
_______cannot be broken up into smaller units since they do not react with water.
Nonsaponifiable lipids
The most frequently encountered lipid building block is ______
Fatty acids
A lipid is any substance of biochemical origin that is?
- insoluble in water but soluble in nonpolar solvents
Which of the following is not a biochemical function classification for lipids?
- Biochemical function classification of lipids are EMEMP
The saponifiable and nonsaponifiable classification system for lipids is based on?
- Lipid behavior in basic solution
2.2 TYPES OF FATTY ACIDS
______ a naturally occurring monocarboxylic acid.
fatty acids
____ always contain an even number of carbon atoms and have a carbon chain that is unbranched
fatty acids
It is a characterization of fatty Acids based on carbon length
(LMS) [Long-chain, medium-chain and short chain]
C12 to C26
long chain
C8 and C10
medium-chain
C4 and C6
short-chain
what are the 3 classification of fatty acids based on carbon-carbon bonds ?
[SFA, MUFA, PUFA]
___ a fatty acid with a carbon chain in which all carbon–carbon bonds are single bonds
SFA
____ a fatty acid with a carbon chain in which one carbon–carbon double bond is present
MUFA
In biochemically important MUFAs, the configuration about the double bond is nearly always__
CIS
_____a fatty acid with a carbon chain in which two or more carbon–carbon double bonds are present
PUFA
The fatty acids present in naturally occurring lipids almost always have the following three characteristics:
- An unbranched carbon chain 2. An even number of carbon atoms in the carbon chain
- Double bonds, when present in the carbon chain, in a cis configuration]
It is to specify double-bond positioning within the carbon chain of an unsaturated fatty acid, the preceding notation is expanded by adding the Greek capital letter
DELTA
18:0
STEARIC ACID
18:3
Delta 9,12,15) [ARACHIDONIC ACID]
double-bond positioning within the carbon chain of MUFA’s generally at
DELTA 9
These family relationships become apparent when double-bond position is specified relative to the methyl (noncarboxyl) end of the fatty acid carbon chain. Double-bond positioning determined in this manner is denoted by using the Greek lowercase letter
OMEGA
_____ _____location of the first two additional double bonds in PUFAs
DELTA 12 AND DELTA 15
A PUFA with the structural parameters
20:4(D5,8,11,14). [ARACHIDONIC ACID]
18:0
Stearic acid
an unsaturated fatty acid with its endmost double bond three carbon atoms away from its methyl end
OMEGA-3
an unsaturated fatty acid with its endmost double bond six carbon atoms away from its methyl end.
OMEGA-6
14:0
Palmitic Acid
12:0
lauric acid
20:0
arachidic acid
18:1 Delta-9 omega-9
oleic acid
18:2 D9,12
linoleic acid
16:1 Delta-9 omega-7
palmitoleic acid
18:3 D9,12,15 omega-3
linolenic acid
20:4 D5,8,11,14 omega-6
arachidonic acid
20:5 D5,8,11,14,17 omega-3
EPA eicosapentaenoic acid
22:6 Delta 4,7,10,13,16,19 omega-3
DHA (docosahexaenoic acid
In which of the following pairs of fatty acids are both members of the pair polyunsaturated fatty acids
- 18:2 acid and 18:3 acid
Which of the following statements concerning fatty acid is correct?
- They are rarely found in the free state in nature
The double bond present in a monounsaturated fatty acid almost always
- is in a cis-configuration
Which of the following fatty acids is ab omega-6 fatty acids?
CH3-(CH2)4- CH=CH-(CH2)8—COOH
● for fatty acids is a direct function of carbon chain length (solubility decreases as carbon chain length increases___
water solubility
● The physical properties of fatty acids, and of lipids that contain them, are largely determined by the
length and degree of unsaturation of the fatty acid carbon chain
● essentially insoluble in water
long-chain fatty acids
● have a slight solubility in water
short-chain fatty acids
● for fatty acids are strongly influenced by both carbon chain length and degree of unsaturation (number of double bonds present).
increases as carbon chain length increases) [Melting points]
● The greater the degree of unsaturation, the greater the reduction in ___
melting points
_____ tend to be solids at room temperature
long-chain saturated fatty acids
_____ tend to be liquids at room temperature
long-chain unsaturated fatty acids
● The greater the number of double bonds, the less efficient the ________As a result, unsaturated fatty acids always have fewer intermolecular attractions, and therefore lower melting points, than their saturated counterparts
packing
The double bonds in unsaturated fatty acids, which generally have the cis configuration, produce________ in the carbon chains of these molecules. These prevent unsaturated fatty acids from packing together as tightly as saturated fatty acids
bends
In which of the following pairs of fatty acids does the first listed acid have a lower melting point than the second listed?
- 18:2 acid and 18:0 acid
In which of the following pairs of fatty acids does the first listed acid have a greater water solubility than the second listed acid?
- 16:0 acid an 18:0 acid
____ most widespread energy-storage material within cells
carbohydrate glycogen
_____ concentrated primarily in special cells (adipocytes) that are nearly filled with the material
[Triacylglycerol]
Adipose tissue containing these cells is found in various parts of the body ___
under the skin, in the abdominal cavity, in the mammary glands, and around various organs
● much more efficient at storing energy than is glycogen because large quantities of them can be packed into a very small volume is
Triacylglycerol
● most abundant type of lipid present in the human body
energy-storage lipids
● The alcohol involved in triacylglycerol formation is always
Glycerol
● In terms of functional groups present, triacylglycerols are?
triesters
● a compound produced from the reaction of an alcohol with a carboxylic acid.
ester
● three-carbon alcohol with three hydroxyl groups
triacylglycerol
● In the esterification reaction producing a triacylglycerol, a single molecule of glycerol reacts with__________ each of the three hydroxyl groups present is esterified
3 fatty acid molecule
____ is a lipid formed by esterification of three fatty acids to a glycerol molecule
triacylglycerol
___ the portion of a carboxylic acid that remains after the -OH group is removed from the carboxyl carbon atom
acyl group
● An older name that is still frequently used for a triacylglycerol is?
triglyceride
______ is a triester formed from the esterification of glycerol with three identical fatty acid molecules
simple triacylglycerol
___ molecules contain three fatty acid residues (three acyl groups) attached to a glycerol residue
triacylglycerol]
____ is a triester formed from the esterification of glycerol with more than one kind of fatty acid molecule
mixed triacylglycerol
● Is a triacylglycerol mixture that is a liquid at room temperature (25C).
oil
● composed largely of triacylglycerols in which saturated fatty acids predominate, although some unsaturated fatty acids are present. Such triacylglycerols can pack closely together because of the “linearity” of their fatty acid chains higher melting points obtained from animals
saturated fatty acids are more prevalent
fat
● is a triacylglycerol mixture that is a solid or a semi-solid at room temperature (25C).
fat
● contain triacylglycerols with larger amounts of mono- and polyunsaturated fatty acids than those in fats. Such triacylglycerols cannot pack as tightly together because of “bends” in their fatty acid chains
come from plants, although there are also fish oils
lower melting points.
unsaturated fatty acids are more prevalent
oil
● highly saturated. This oil is a liquid not because it contains many double bonds within the fatty acids but because it is rich in shorter-chain fatty acids, particularly lauric acid
coconut oil
How many structural “subunits” are present in the block diagram for a triglycerols
4
How many different simple triglyceride molecules can be produced that include glycerol, stearic acid and palmitic acid as part of their structure?
zero
How many ester linkages are present in a triacylglycerol molecule?
3
How many different mixed triglyceride molecules can be produced that include glycerol, stearic acid and palmitic acid as part of their structure?
- four
Which of the following is a distinguishing characteristic between fats and oils?
- physical state at room temperature
Unsaturated fatty acid residues are structural components of?
- both fats and oils
● bad fat, increase heart disease risk
saturated fat
● Total fat intake recommendation
(30% of total calories—with up to 15% coming from monounsaturated fat, up to 10% from polyunsaturated fat, and less than 10% from saturated fats.)
● Good fat, decreases both heart disease and breast cancer risk ,include olive, avocado, and canola oils, help reduce the stickiness of blood platelets. This helps prevent the formation of blood clots and may also dissolve clots once they form
monounsaturated fat)
● both good and bad fat, reduce heart disease risk but promote the risk of certain types of cancers, (polyunsaturated fat)
● Good sources of MUFA
Tree nuts and Peanuts
● In the 1980s, researchers found that the Inuit people of Greenland exhibit a low incidence of heart disease despite having a diet very high in fat. This contrasts markedly with studies on the U.S. population, which show a correlation between a high-fat diet and a high incidence of heart disease. What accounts for the difference between the two peoples?
(The Inuit diet is high in omega-3 fatty acids (from fish), and the U.S. diet is high in omega-6 fatty acids (from plant oils)
also called fatty fish because of the extra amounts of fat they have for insulation against the cold, contain more omega-3 acids than leaner, warm-water fish
Cold-water fish
● cold water fishes high on omega 3
albacore tuna, salmon, and mackerel)
● leaner warm fish
cod, catfish, halibut, sole, and snapper
● In 2001, the FDA gave approval for manufacturers of baby formula to add the fatty acids_________ and _______to infant formulas. Human breast milk naturally contains these acids, which are important in brain and vision development. Because not all mothers can breast-feed, health officials regulate the ingredients in infant formula so that formula-fed babies get the next best thing to mother’s milk.
● DHA (docosahexaenoic acid) and AA (arachidonic acid)
● Two essential fatty acids that are needed for proper membrane structure and (2) serve as starting materials for the production of several nutritionally important long chain omega-6 and omega-3 acids
Linoleic acid and Linolenic acid)
● fatty acid needed in the human body that must be obtained from dietary sources because it cannot be synthesized within the body, in adequate amounts, from other substances
(essential fatty acids
___ is the primary member of the omega-6 acid family, the starting material for the biosynthesis of arachidonic acid, the major starting material for eicosanoids— substances that help regulate blood pressure, clotting, and several other important body functions ____
18:2 , Linoleic
______ is the primary member of the omega-3 acid family, the starting material for the biosynthesis of two additional omega-3 fatty acids— EPA and DHA____
18:3, (linolenic)
● What happens if the essential acids are missing from the diet?
● (the skin reddens and becomes irritated, infections and dehydration are likely to occur, and the liver may develop abnormalities)
● important constituents of the communication membranes of the brain and are necessary for normal brain development, also active in the retina of the eye
● EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid)
● substances that replicate the taste, texture, and cooking properties of fats but are themselves not lipids
artificial fats
● Omega-3 Acids
[linolenic acid (18:3); eicosapentaenoic acid (20:5); docosahexaenoic acid (20:6)]
● Omega 6 acids
linoleic acid (18:2); arachidonic acid (20:4)]
In terms of human body response to dietary fat, which of the following is considered to be “good fat”
- monounsaturated fats
Current dietary recommendations for Americans, relative to omega-3 and omega-6 fatty acids, include a recommended increase in?
- both omega-3 and omega-6 fatty acid intake
Linolenic acid and linoleic acid, the essential fatty acids, are, respectively,
- 18:2 and 18:3 fatty acids