Lipids Structure And Digestion Flashcards
Lipids are components of?
plants and animal tissues
On a physical nature, lipids are relatively insoluble in?
water
On a physical nature, lipids are soluble in?
organic solvents, such as hexane, ether, and chloroform
Chemically, lipids are organic compounds and esters of?
fatty acids and glycerol (a 3 C compound) or some other alcohol.
(a 3 C compound)
glycerol
are the primary storage form of energy (e.g., oil in seed) and serve as an animal’s body’s “savings account.”
Fats
the abdominal fat pads in chicken and back fat in pigs are mostly?
triglycerides
Esters of fatty acid with alcohol
Simple lipid
what is the molecular structure of triglycerides
1 glycerol + 3 fatty acids
Compounds of lipids:
A. Glycolipid
B. Lipoproteins
C. Phospholipids
Lipid Classifications:
A. Simple lipid
B. Compound
C. Derived Lipids
like triglycerides are more common and are an important component in animal rations (e.g., vegetable oil and animal fats such as tallow or lard).
Simple lipids
are composed of a lipid plus a nonlipid molecule
Compound lipids
(lipid + protein)
Lipoprotein
Lipoprotein (lipid + protein) are examples of compound lipids and are used for?
lipid transport
Within the animal body, compound lipids are more important in?
physiology and metabolism
Nutritionally, ? are excellent sources of energy and are essential to the survival of animals.
fats
Fats are the sole source of (those that cannot be made by the body) for animals
Essential fatty acids
can also provide fat-soluble vitamins.
Fats
very minimal in livestock because feeds are supplemented with?
vitamins
The most important role of dietary fat is to provide
essential fatty acids
As the fat content of the diet increases, the ? of the diet goes up.
energy density
Physically, the addition of fats is associated with the improvement of?
feed quality
Physically, the addition of fats is associated with the reduction of dust in?
feed
Physically, the addition of fats is associated with the reduction of ? during processing
feed particle separation
Physically, the addition of fats is associated with increase in?
- palatability
- digestive lubrication
- feed digestibility
What is the extracted oil of coconut?
Crude coconut oil or copra oil
What is the end product of processed coconut oil?
Cooking oil
Most commonly used for feed formulation?
Crude coconut oil or copra oil
Examples of macro ingredients of feeds?
Rice, soybean meal, corn and wheat
Micro ingredients of feeds?
Vitamins, minerals and toxin binders
Fatty acids are the main players in?
lipid nutrition
are the main players in lipid nutrition. This is due to their diversity in structure, composition, and metabolizability.
Fatty acids
The molecular composition of a fatty acid includes a ? at opposite terminals of a hydrocarbon backbone
hydrophilic carboxyl group (−COOH) and a hydrophobic methyl group (−CH3)
are attached to the glycerol molecule
three fatty acids
three fatty acids are attached to the?
glycerol molecule
In most cases, three fatty acids are attached to the glycerol molecule and are called?
triacylglycerol
The three fatty acids in triacylglycerol can differ in
chain length and number of double bonds
Fatty acid composition and structure determine the?
physical property and nutritional quality of fats
when there is a predominance of saturated fats in the triacylglycerol, fat tends to?
solidify
when there is a predominance of unsaturated fats, fat tends to?
liquefy
Fatty acids are classified into three families based on the presence (or absence) of?
double bonds in the hydrocarbon chain.
Fatty acids are classified into three families based on the presence (or absence) of double bonds in the hydrocarbon chain. These include:
- saturated fatty acids
- monounsaturated fatty acids
- polyunsaturated fatty acids (PUFAs).
no double bonds in fatty acid
Saturated fatty acids
presence of double bonds (could be one or two) in fatty acids
Unsaturated fatty acids
more than two double bonds in fatty acids
Polyunsaturated fatty acids
are “saturated” with hydrogen or straight chains with no double bonds
Saturated fatty acids
When there is a predominance of saturated fats in the glycerol moiety, the triacylglycerol tends to be?
solid
Why do triacylglycerols with a predominance of saturated fatty acids tend to be solid?
They “pack” very tightly in the membrane.
contain one or more double bonds between adjacent carbon atoms in the hydrocarbon chain.
Unsaturated fatty acids
Unsaturated fatty acids contain one or more double bonds between adjacent carbon atoms in the hydrocarbon chain.
Unsaturated fatty acids may be either?
mono (one double bond) or polyunsaturated (more than two double bonds)
When there is a predominance of unsaturated fats, the triglyceride tends to be liquid because unsaturation gives a ? in their structure and they cannot pack as tightly as saturated fats
“bend”
Polyunsaturated fatty acids are commonly called?
“PUFA”
Due to these extra double bonds, PUFAs tend to be more ? when compared to the straight chain structure of a saturated fat
“round”
Nutritionists designate the term ? to denote the position of double bonds in the carbon chain in a PUFA.
omega (ω) or “n”
is the first carbon with a double bond counting from the methyl end (CH3) of the carbon chain.
omega carbon
The two PUFA classifications are:
- omega-6
- omega-3
omega-6 also called?
n-6, or ω-6
omega-3 also called?
n-3, or ω-3
omega-3 fatty acid will have the first double bond at the ? when counted from the methyl (CH3) end
third carbon
omega-6 fatty acids will have the first double bond at the ? when counted from the methyl (CH3) end
sixth carbon
The locations of the double bonds are also indicated by the Greek letter ?, in some chemistry or biochemistry textbooks.
Δ, “delta”
This term denotes the position of double bonds from the carboxyl end.
delta
In nonruminant, or monogastric, animals such as pigs, this has to be supplied in the diet
α-linolenic acid and linoleic acid
The linoleic acid and a-linolenic acid is essential because monogastric animals do not have the ability to?
Insert double bond in n-3 &n-6 locations
carnivores such as cats need this fatty acid in their diets.
arachidonic acid (C20:4 n-6)
In nutrition, the term ? means animals cannot synthesize it to meet their requirements.
“essential”
Essential fatty acids include the following:
- Linoleic acid (C18:2 n-6)
- a-Linolenic acid (C18:3 n-3)
- Arachidonic acid (C20:4 n-6; in true carnivores, e.g., cats)
Fatty acids are commonly expressed by their
trivial names (e.g., linoleic acid) or their associated shorthand notations (C18:2 n-6)
includes the number of carbon atoms and double bonds.
The shorthand nomenclature of a fatty acid
in linolenic acid, stands for 18 carbon atoms and three double bonds, of which the first double bond is at the third carbon atom from the methyl carbon.
C18:3 n-3
Unsaturated fatty acids can form geometric isomers, with either ?, depending on the stereo-conformation of groups around a double bond.
cis or trans
What are the geometric isomers of most natural fatty acids of animal and plant origin
Cis type
What are the geometric isomers of bacterial origin?
They contain both cis and trans types
What geometric isomers conjugated linoleic acid (CLA) is?
trans fatty acid
conjugated linoleic acid (CLA) is a trans fatty acid present in?
cow’s milk or other ruminant food like beef
conjugated linoleic acid (CLA) is a trans fatty acid present in cow’s milk or other ruminant food like beef and is produced by?
rumen microbes during the biohydrogenation process
In CLA, the two double bonds lack a methylene group separating them, have a conjugated arrangement, and are called?
natural trans fats
Trans fats such as ? have received considerable attention due to their several health-promoting effects.
Conjugated linoleic acid
have different health effects when compared with “natural” trans fats such as CLA.
synthetic trans fats
is an intermediate conjugated fatty acid formed during biohydrogenation, or conversion from unsaturated to saturated fatty acid.
Conjugated linoleic acid
Most natural fats occur in the?
cis form
The exception is a trans fat called ?, which is produced by rumen microbes.
conjugated linoleic acid (CLA; C18:2 n-6)
(lipids with phenanthrene ring–like structures)
Sterols
are the most abundant steroid in the human diet.
Sterols
is the best known steroid (fat-soluble substance containing a steroid nucleus) and is the precursor of many other substances such as vitamin D, bile acids, sex hormones, and corticosteroid hormones.
Cholesterol
An important component of animal tissues, egg yolks, and cell membranes
Cholesterol
is partly by dietary intake and partly by biosynthesis from acetyl CoA
cholesterol synthesis
Excess cholesterol is stored in?
arteries
Excess cholesterol is stored in arteries and can lead to?
atherosclerotic plaque formation and cardiovascular disorders.
Excretion of cholesterol is through?
bile acid formation
Plant cells do not contain cholesterol but instead contain other sterols called?
phytosterols
Serve as energy reserves for the plant or animal fat
Triglycerides
Of unsaturated fatty acids is the second major transformation that dietary lipids
can undergo in the rumen
Biohydrogenation process
