Animal Nutrition Test 3 Flashcards

1
Q

Carbs are:

A

Polyhydroxyaldehydes or polyhydroxyketones, or substances that yield them on hydrolysis

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2
Q

Gum is a:

A

Carb

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3
Q

What percentage of an animals body is carbs?

A

Less than 1%

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4
Q

Carbs form what percent of the dry weight of forages? Seeds?

A

70%, up to 85%

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5
Q

Feeds classified as carbs generally occupy what percent of the diet on a weight basis?

A

Over 80%

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6
Q

Major function of carbs:

A

Dietary energy

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7
Q

Energy reactant in photosynthesis

A

686 Kcal

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8
Q

Chemical composition by % molecular weight of carbs is:

A

C: 40%
H: 7%
O: 53%

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9
Q

How much more energy/calories does fat contain than carbs on an equal weight basis?

A

2.25x

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10
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Arabinose

A

Pentose monosaccharide

Polysaccharides found in: araban and pectin

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11
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Xylose

A

Pentose monosaccharide

Found in polysaccharides, corn cobs, and wood

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12
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Ribose

A

Pentose monosaccharide

Found in nucleic acids NOT IN POLYSACCHARIDES

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13
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Glucose

A

Hexose monosaccharide

Found in disaccharides (literally all of them that I list), polysaccharides, honey, fruits, and plant sap

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14
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Fructose

A

Hexose monosaccharide

Found in disaccharides and inulin

The sweetest monosaccharide, the only ketone hexose

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15
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Galactose

A

Hexose monosaccharide

Found in milk (lactose disaccharide)

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16
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Mannose

A

Hexose monosaccharide

Found in polysaccharides

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17
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Sucrose (table sugar)

A

Disaccharide, glucose + fructose

Found in sugar cane and beets

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18
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Maltose

A

Disaccharide, glucose + glucose (4-a linkage)

Found in starchy plants and roots

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19
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Lactose

A

Disaccharide, glucose + galactose

Found in milk

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20
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Cellobiose

A

Disaccharide, glucose + glucose (4-B linkage)

Found in the fibrous portion of plants

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21
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Raffinose

A

Trisaccharide/oligosaccharide, glucose+fructose+galactose (sucrose+galactose)

Found in certain varieties of eucalyptus, cottonseed, and sugar beets (sucrose is found in sugar beets too!)

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22
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Araban

A

Polysaccharide pentosan made of arabinose

Found in pectins (just like arabinose)

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23
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Xylan

A

Polysaccharide pentosan made of xylose

Found in corn cobs and wood (just like xylose)

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24
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Starch

A

Polysaccharide hexosan made of glucose (maltose)

Found in grains, seeds, tubers, rhizomes, and fruits

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25
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Dextrin

A

Polysaccharide hexosan, breakdown unit of starch so 3-8 units of glucose

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26
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Cellulose

A

Polysaccharide hexosan made of 3,000-5,000 units of glucose (cellobiose)

Found in the cell wall of plants (the fiber found in the stem, leaves, and roots)

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27
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Glycogen

A

Polysaccharide hexosan made of glucose so it’s very similar to starch

Found in the liver and muscle of animals

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28
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Inulin

A

Polysaccharide hexosan made of fructose

Found in potatoes, tubers, and artichokes

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29
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Hemicellulose

A

Mixed polysaccharide that is a mixture of pentoses (mostly) and some hexoses

Found in fibrous plants

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30
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Pectins

A

Mixed polysaccharide that is a mixture of pentoses, hexoses, and salts of complex acids

Found in citrus fruits and apples

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31
Q

Classify the following carb as either a monosaccharides (pentose or hexose), disaccharide, trisaccharide, polysaccharide (pentosan or hexosan), or mixed polysaccharide.

Gums (partially oxidized to acids)

A

Mixed polysaccharide made up of pentoses and hexoses

Found in acacia trees and some plants

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32
Q

Oligosaccharide has how many sugars?

A

3-10

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33
Q

Glycose=

A

A monosaccharide

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34
Q

What are the only monosaccharides that occur in free form in nature?

A

Glucose and fructose

Both are WATER SOLUBLE and sweet

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35
Q

Are pentoses dietary essentials?

A

No, they can be made from hexoses, protein, and glycerol

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36
Q

What is ribose found in?

A

ATP, ADP, riboflavin, and RNA

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37
Q

Digestibility of hemicellulose

A

Partially digestible because of acidic conditions in the stomach

Insoluble in boiling water, soluble in dilute alkali, readily degraded by dilute acid

Mammals don’t make enzymes to digest it

Closely associated with lignin in the cell wall

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38
Q

Most abundant carbs found in nature

A

Hexoses

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39
Q

2 functions of hexosans

A

1) Make up a major part of the animal and human diet (starch and cellulose)
2) they serve as both fuel and intermediates in metabolic pathways

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40
Q

2 functions of glucose in metabolism:

A

Glucose is the major carb used for energy at the cellular level. All digested dietary carbs are converted to glucose, making it a dietary essential

Major circulating carb in the blood

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41
Q

Haworth perspective

A

The position of the H and OH groups on C1 determines if the compound is in alpha or beta form

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42
Q

Where are derivatives of galactose found?

A

Brain and nervous tissue

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43
Q

What 1 species can’t use galactose?

A

Poultry, they don’t have lactase

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44
Q

Form of inulin found in plants?

A

Mannans

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45
Q

Order these from sweetest to nonsweetest:

Sucrose
Glucose
Fructose
Lactose
Maltose
Saccharine
Aspartame
A

Saccharine, aspartame, fructose, sucrose, glucose, maltose, lactose

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46
Q

Other sources of sucrose besides sugar cane and sugar beets?

A

Ripe fruits, tree sap (maple sugar), vegetable, and sorghum (molasses)

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47
Q

What animal doesn’t have sucrase activity?

A

Baby pigs until 7 days old

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48
Q

How does maltose get its name?

A

It’s made commercially from starch via the malting process

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49
Q

What things can split cellobiose?

A

Microbial enzymes, fungal enzymes, or acid

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50
Q

What proportion of the solids in milk is lactose?

A

1/2

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51
Q

Methods of alleviating lactose intolerance?

A

1) put B-galactosidase in milk before drinking it (break the bond and it’ll taste sweeter)
2) drink lactobacillus acidophilus milk (makes a different bacterial population in large intestine)

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52
Q

In cultured products such as yogurt, what percentage of lactose is fermented to lactic acid?

A

60%, better for lactose intolerant people

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53
Q

In what form do animals obtain most of their dietary carbohydrate?

A

Polysaccharide

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54
Q

Why do fruits get sweeter when ripening?

A

Conversion of starch to sugars

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55
Q

Amylose makes up what percentage of starch in most plants?

A

25-30%

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56
Q

Amylopectin makes up what percentage of starch in most plants?

A

70-75%

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57
Q

Characteristics of amylose

A

Soluble in hot water
Straight chains of glucose
a-1,4-linkage only
Helix

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58
Q

Characteristics of amylopectin

A
Insoluble in water 
Branched chains of glucose (more sites for enzymes to attach so more digestible than amylose)
a-1,4-linkage AND a-1,6 cross linkages 
Phosphorous found
One of the largest MW in nature
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59
Q

Frequency of phosphorus found in amylopectin?

A

1 in every 400 glycose units

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60
Q

Molecular weight of amylopectin?

A

A million or more

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61
Q

When you hydrolyze or apply high heat to starch, what do you get?

A

Dextrin (3-8 glucose units)

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62
Q

Glycogen is what percent of weight weight of liver?

A

Usually 2-8% in most species, can be up to 10%

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63
Q

Is glycogen water soluble?

A

Yes (pure polymer of glucose, which is water soluble)

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64
Q

What level will liver glycogen be at after 24 hours of fasting?

A

0

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65
Q

Most abundant substance in the plant kingdom?

A

Cellulose

Also the single most abundant organic compound in the world

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66
Q

Cellulose occupies what percentage of the dry matter of all vegetation?

A

About 50%

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67
Q

Is cellulose soluble in water?

A

No

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68
Q

Name the 3 heteropolysaccharides

A

Pectin, hemicellulose, and gums

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69
Q

Composition of hemicellulose

A

60-80% xylose and arabinose (pentoses), galactose, glucose, and others

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70
Q

Hemicellulose covalently links to ____ and then hydrogen bonds to _____

A

Pectin, cellulose

Remember lignin is close by too

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71
Q

Digestibility of pectin

A

Depends on microbes so questionable value to monogastrics

Much of it is digested, even by humans, however. So it must be a readily fermentable fraction for the microbes for to be true

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72
Q

Function of pectin

A

Holds water!

Used as diarrhea medicine, given to cows in the form of beet pulp to make ruminoreticulum expand and cow has spring of rib

Also used in dairy rations as fiber to balance fiber fraction

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73
Q

Pectin is similar to:

A

Hemicellulose

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74
Q

What is starch’s job?

A

Energy reserve in roots, tubers, and seeds

This is why glycogen is called “animal starch” because it’s an energy reserve in animals

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75
Q

How much lipid is in most diets?

A

Usually less than 5%, carb is much more plentiful energy form in food

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76
Q

Ultimate source of energy for most animal cells?

A

Glucose

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77
Q

What classification of carbs can be absorbed form the gut?

A

Monosaccharides

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78
Q

Digestion of amylose and amylopectin

A

Digested by the same enzymes because hydrolysis of both to glucose is similar

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79
Q

Lignin is a mix of:

A

Polymers and phenolic acid

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80
Q

Characteristics of lignin

A

Increases with plant age

Found with hemicellulose and cellulose in cell walls

Effects bioavailability of cellulose and hemicellulose for microbial use

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81
Q

Sources of lignin

A

Legumes are high in lignin

Grasses are intermediate in lignin

Veggies and cereal are low in lignin

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82
Q

Can pigs use VFAs?

A

Yes, microbes in large intestine can make VFAs from fiber

These VFAs can provide some of the energy required for maintenance

May be as much as 30% of the digestible energy intake due to a cellulolytic enzyme in the pig large intestine

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83
Q

3 major groups of microbes found in the rumen?

A

Small bacteria (largest in microbial mass), ciliated protozoa, and fungi

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84
Q

Areas of monosaccharide absorption

A

Duodenum and Jejunum > ileum> stomach and large intestine

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85
Q

Disaccharidase deficiency

A

Serious GI upsets

No sucrase in young mammals and ruminants = severe diarrhea or death when fed large amounts of sucrose

No lactase in adult pigs and some humans= diarrhea when fed lactose

Fewer starch-splitting enzymes in ruminants than nonruminants

86
Q

Absorption rate of soluble carbs? Does it vary greatly from animal to animal?

A

90%, no

87
Q

Factors affecting the rate of digestion of starch

A

Particle size, nature of the starch (amylose vs amylopectin), interactions of starch with proteins and fat, and the presence of antinutrients (tannins, phytate, saponins, and enzyme inhibitors)

88
Q

What happens to monosaccharides other than glucose after absorption?

A

If they weren’t turned into glucose by the mucosa cell during absorption, then they’ll be turned to glucose in the liver. The glucose can either be turned to fat or glycogen if it’s being stored, but fat is much more likely than glycogen

89
Q

Purpose of glycogen

A

It can be hydrolyzed RAPIDLY back to glucose (fat is slower!) or vice verse to keep circulating blood glucose within a narrow range

90
Q

Glycogenesis

A

Glucose –> glycogen

91
Q

Glycogenolysis

A

Glycogen –> glucose

92
Q

What hormones control blood sugar regulation?

A

Insulin and glucagon from the pancreas

93
Q

Oxidative phosphorylation

A

Using the energy of oxidation (giving electrons from a substrate to oxygen) to phosphorylate ADP to ATP

Driving force for absorption of nutrients from the GI tract and synthesis of the 4 macromolecules

94
Q

Gluconeogenesis

A

When the body tissues (liver and sometimes kidneys) make glucose from noncarbs like lipids and amino acids.

95
Q

Glucogenic

A

When metabolized it gives rise to a net increase in glucose

96
Q

Amino acids that are glucogenic only:

A

All the nonessential amino acids (everything that’s not MATT HILL VP! Remember arg, three Tylers? Let’s drown him in phenol)

Some of the essential amino acids: Met, His, Cys, Val, Thr, Trp, Arg (I met his sister Valerie three times, she tripped down the stairs and yelled arg)

97
Q

Amino acids that are both glucogenic and ketogenic

A

Tyr, Ile, Phe, Lys (Tyler said, “I’ll make you feel like you have lice”)

98
Q

Amino acid that is ketogenic only

A

Leucine

99
Q

What happens when ingestion of carbs exceeds current needs?

A

Glucose –> pyruvate –> fat

100
Q

The amino acids used for gluconeogenesis or for energy enter the TCA as:

A

Acetate, pyruvate, or a-ketoglutarate

101
Q

Two fates of pyruvate

A

Converted to acetyl CoA in the mitochondria

Reduced to lactate in the cytoplasm by oxidation of NADH

102
Q

How much total energy is released in the conversion of glucose to CO2 and water?

A

673 kcal (remember: 686 reactant for photosynthesis)

103
Q

What is the efficiency of the conversion of the free energy of oxidation of glucose?

A

40-60%

104
Q

What animals does ketosis affect?

A

Lactating cattle and pregnant sheep

also swine during starvation, pregnant ewes, and dairy cows with B12 deficiency

105
Q

Define ketosis

A

An excess of ketones (acetone, acetoacetate, and B-hydroxybutyrate) in TISSUES bc of a disorder in CARB OR LIPID (energy) metabolism

Ketonemia/acetonemia = increased ketones in BLOOD

Ketonuria = increased ketones in URINE

Treat by restoring normal blood glucose because CHARACTERIZED BY LOW BLOOD GLUCOSE

106
Q

Rumen microbes have enzymes that can hydrolyze cellulose present in cell walls in:

A

Leaf, stem, and outer bran layer of seeds

107
Q

What can termites do

A

Break down lignin (chief constituent of trees)

108
Q

Extensins

A

PROTEINS that are in the structural components of plants. Proteolytic enzymes can’t degrade them so they have low bioavailability

109
Q

Van Soest

A

Neutral detergent gives NDF (cellulose, hemicellulose, and lignin)

Acid detergent gives ADF of lignin and cellulose and ADS of hemicellulose

H2SO4 digestion gives insoluble lignin and soluble cellulose

Hemicellulose > cellulose > lignin based on solubility

110
Q

How might recombinant DNA technology assist in improving fiber digestion?

A

Cloning cellulases to change microbial activity so that it can break the cellulose-hololignin bond

Produce superior cellulolytic microbes

111
Q

Is lignin a carb?

A

No

112
Q

Amorphous

A

No particular structure

Lignins structure depends on the plant species

113
Q

Lignin

A

Resistant to degradation by acids or alkali

Reduces digestibility of PROTEIN too!

114
Q

When does the amount of lignin in a plant escalate?

A

Around the time of setting of seed. Thus, many forages are harvested when they’re beginning to bloom or right before

115
Q

What things can break the bond between lignin and other things AND degrade the lignin itself?

A

AEROBIC microbes and fungi

Strong alkali can only break the bond- it leaves the lignin intact

Note: rumen organisms can’t do either!

116
Q

Carb fractions found in the stem, leaf, and seed?

A

Fiber, monosaccharide, and starch

117
Q

Fiber, monosaccharide, and starch in the stem

A

Fiber: lots of it
Monosaccharide: a little being transported from leaves to seeds
Starch: none

118
Q

Fiber, monosaccharide, and starch in leaves

A

Fiber: some
Monosaccharide: lots from photosynthesis
Starch: none

119
Q

Fiber, monosaccharide, and starch in seeds

A

Fiber: some (but not much) because of hull/seedcoat
Monosaccharide: some (but not much) as precursor of starch
Starch: lots to nourish the seedling

120
Q

What percentage of grains is starch?

A

60-80%

121
Q

How digestible is starch?

A

80-90% digestible

122
Q

What percentage of grains is cell wall?

A

Less than 15%

123
Q

Cell wall and lignin content of green pasture vs dormant pasture

A

Green pasture has less cell wall content and less lignin

Dormant pasture has more of both

124
Q

Cell wall and lignin content of hay vs silage

A

Exactly the same for both

125
Q

What percentage of a hull/seedcoat is cell wall?

A

60-80%

126
Q

How digestible are hulls/seedcoats?

A

Highly digestible, 60-80% because they only have 2-3% lignin

127
Q

3 things are lipids have in common

A

1) insoluble in water but soluble in organic solvents
2) they are actually or potentially fatty acid esters
3) utilized by living organisms

128
Q

Elemental composition of lipids by % MW:

A

C: 77%
H: 12%
O: 11%

129
Q

Classifications of the lipids of nutritional importance:

A

Simple lipids, compound lipids, derived lipids, sterols, and terpenes

130
Q

Simple lipids

A

Fatty acids+alcohols

Fats and oils (these make up largest fraction of lipids in most material), and waxes (waxes are the only ones with an alcohol different than glycerol. They’re unimportant and not used well by body)

131
Q

Energy value of fats vs carbs

A

9.45 kcal/gram for fat, 4.1 kcal/gram for carbs

132
Q

Compound lipids

A

Fatty acid + lipid + SOMETHING ELSE

Phospholipids, glycolipids (sometimes contain N), and lipoproteins. The last two are used for metabolism and are scarce

133
Q

Derived lipids

A

Substances derived from simple or compound lipids by hydrolysis

Fatty acids, glycerol, and other alcohols

134
Q

Sterols

A

Lipids with complex phenanthrene-type structure (used for metabolism, scarce)

135
Q

Terpenes

A

Have isoprene-type structure

Unimportant, not used well by the body

136
Q

Most important lipids in nutrition

A

Fatty acids, glycerol, mono-, di-, and triglycerides, and phospholipids

137
Q

All neutral fats contain:

A

Glycerol

138
Q

Chain length of fatty acids

A

Can be from 2-24 carbons long (even number), but the most common fatty acids have 16-18 carbons

139
Q

Naturally occurring variations in fatty acids:

A

Odd number of carbons, branched chains, or hydroxy acids

These are less plentiful but found in ruminants due to microbial synthesis

140
Q

Almost all naturally occurring lipids contain one or more:

A

Fatty acid

141
Q

Which are more reactive: saturated or unsaturated fatty acids?

A

Unsaturated bc of the double bond

142
Q

Omega-3 and omega-6 fatty acids

A

Long chain unsaturated fatty acids in depot fats (adipose) of fish

They consist of: linoleic acid, eicosapentaenic acid, and docosahexaenoic acid (DHA)

Where double bond is is critical to biological activity

143
Q

Carbons and double bonds in linoleic acid?

A

18 C, 3 double bonds

144
Q

Carbons and double bonds in eicosapentaenic acid?

A

20 carbons, 5 double bonds

145
Q

Carbons and double bonds in DHA?

A

22 carbons, 6 double bonds

146
Q

What do fish oils protect against?

A

Atherosclerosis (CHECK THIS ONE)

147
Q

Benefits of CLA isomers to humans?

A

Protect against cancer, diabetes, atherogenesis, and obesity

Modulates immune function and bone growth

148
Q

Primary form of lipid in nature

A

Mono di and triglycerides

149
Q

2 factors that determine physical and chemical properties of fatty acids:

A

Chain length and degree of unsaturation

150
Q

Liquid fat at room temperature

A

Unsaturated or saturated with a chain length less than 10

More than 10 saturated is solid

151
Q

3 tests used to characterize the chemical properties of fats:

A

Saponification number: chain length

Reichert-Meissl (RM) number: proportion of VFAs present

Iodine number: degree of hydrogenation/saturation

152
Q

Common characteristic of a phospholipid

A

Ester phosphorus

153
Q

Function of phospholipids

A

Cell organization, also involved in mitochondrial enzyme systems and lipid transport because of their emulsifying properties

154
Q

Lecithin

A

White, waxy phospholipid that oxidizes to brown in the presence of oxygen

Basically phosphatidyl CHOLINE

Keeps oils and water together (mayonnaise and milk)

155
Q

Steroids and sterols are derivatives of:

A

Cyclopentanoperhydrophenanthrene (phenanthrene ring)

156
Q

Erogsterol + sunlight =

A

Vitamin D

157
Q

In what locations are steroid hormones made from cholesterol?

A

Adrenal cortex, gonads, corpora lutea, and placenta

158
Q

What are adrenal steroids involved in?

A

Carb and protein metabolism, fluid and electrolyte balance, blood pressure regulation, stress resistance, and more

159
Q

What are estrogens and progesterones involved in?

A

Regulate estrus, reproductive cycles, influence protein and nucleic acid and lipid metabolism, and regulate normal bone metabolism

160
Q

What are androgens involved in?

A

Make sex hormones responsible for secondary sex characteristics, sperm maturity, activity of accessory glands of the genital tract, and promotion of N retention

161
Q

Ralgro

A

Pseudosterol used as a growth implant in beef cattle

162
Q

4 major functions of lipids

A

Energy supply, EFAs, carry fat soluble vitamins, and components of membranes

163
Q

Arachidonic acid is the precursor of:

A

Prostaglandins

These are are a type of eicosanoid. Prostaglandins have many metabolic purposes such as lowering blood pressure, stimulating muscle contraction, inhibiting norepinephrine-induced release of fatty acids from adipose, and modulating immune function.

164
Q

Which species requires dietary arachidonic acid?

A

Cat

165
Q

Function of EFA

A

Not completely understood, but they are major parts of phospholipid and cholesterol esters that play a part in cell membranes and lipid transport moieties

166
Q

EFA deficiency symptoms in monogastrics

A
Dull hair coat with possible loss
Scaly skin
Necrosis of tail
Failure to grow
Affected reproduction and lactation
Eventual death
167
Q

3 Sources of fats in livestock diet

A

Plants, pure sources of fat, and protected fat

168
Q

Where do we primarily find fats in plants?

A

Seeds

Oilseeds such as soybeans, cottonseeds, and mung beans contain from 18-25% lipid

169
Q

Grain is the other source of fat in plants (besides seeds). What is the lipid content of corn, milo, wheat, etc?

A

2-4%

170
Q

Pure sources of fat for humans

A

Soybean oil, cottonseed oil, corn oil, etc

171
Q

Pure sources of fat in livestock rations

A

Tallow from beef and lard from hogs

172
Q

The lipids found in feedstuffs are what percent digestible?

A

Normally greater than 80% digestible. Exceptions include wax and cutin

173
Q

How much fat digestion occurs in the stomach?

A

Not much because gastric lipase has a higher optimal pH than the acidic conditions of the stomach

More important in the young where the stomach pH is higher and the fats in milk are already emulsified (lecithin)

174
Q

What 2 things increase the activity of pancreatic lipase?

A

Calcium and the bile salts (emulsify fats into water bc lipase is water soluble)

175
Q

Most dietary fat is in what form?

A

Triglycerides. These are water-insoluble so they are emulsified in the stomach and further in the small intestine. This is a COARSE emulsion accomplished by peristaltic contractions

176
Q

Where does pancreatic lipase work on the emulsion particle? How does bile help the lipase?

A

At the oil-water interface.

Bile helps form the emulsion droplets and also helps to orient the lipase with the triglycerides for hydrolysis

177
Q

Which positions does lipase free the fatty acids from the TG?

A

1 and 3

178
Q

Which position does lipase free the fatty acid from the phospholipid?

A

From the 1 position. Only a lysolecithin is left

179
Q

The bile acids are more effective in the presence of

A

Monoglycerides and lysolecithin. Therefore the digestion products promote further digestion

180
Q

Overview of absorption of fat

A

Bile acids and monoglycerides form micelles. These take up fatty acids (>12) and degrade them. The micelle then goes to the brush border of the jejunum (which is aided by the peristaltic contractions of the gut) and is absorbed into the mucosa cell. Here, monoglycerides and made back into TGs. Next, a chylomicron is made and transported out of the cell via osmotic pressure into the central lacteal of the lymphatic system, to the thoracic duct at the right atrium, and to the body.

181
Q

In the conversion of fats from an emulsion droplet to a micelle, the diameters of the particles is reduced ____ times and the surface area is increased over ____ times

A

100, 10,000

182
Q

Some bile salts are also absorbed in the jejunum. Most are absorbed in the ileum. This system is ____ efficient.

A

95% efficient

183
Q

Chylomicron composition:

A
Triglyceride: 80%
Cholesterol esters: 9%
Phospholipid: 7%
Cholesterol: 2%
Protein: 2%
184
Q

How to make fats from carbs

A

Glucose to pyruvate to acetyl CoA, which can either go to the TCA for energy production or undergo lipogenesis to make SATURATED fatty acids. These then become unsaturated and are used to make TGs, phospholipids, etc.

To get a fatty acid (either saturated or unsaturated) back to acetyl CoA again, do beta oxidation (take 2 carbs off at a time at the carboxyl end until it’s degraded)

185
Q

Whole plants are at a maximum up what percent lipids?

A

5%

186
Q

2 lipids consumed predominantly from ruminants:

A

TG from the seeds and galactolipids from the leaves

187
Q

In the rumen, glycerol is fermented to yield ____

A

Propionic acid

188
Q

What percent of the fats in beef are saturated?

A

50%

189
Q

Which fatty acids are absorbed by rumen microbes?

A

Short chain only!

Remember all fatty acids are made saturated in the rumen

Short chain can also be absorbed in rumen or passed down the tract.

190
Q

Fate of long chain fatty acids in the rumen

A

They form water-soluble salts (soaps) and pass on for absorption in the small intestine

-not absorbed in rumen or used by microbes! Just pass on in the form of soaps

191
Q

What controls adipose tissue?

A

Nervous and endocrine system, so there’s nerves and blood in adipose

192
Q

As the percent of fat in the body increases, the percent of water in the body:

A

Decreases

193
Q

Lipid concentration in milk

A

1.5%-50% in seals

Nearly all milk lipid is TG (mammary glands actively make TG and secrete it into milk)

194
Q

Sources of fatty acids in milk:

A

Circulating TG

Circulating nonesterified fatty acids originating in adipose tissue

De novo fatty acid synthesis in mammary gland

195
Q

Principal fatty acid precursor in monogastrics

A

Glucose (turns into acetyl CoA to undergo lipogenesis to make saturated FAs to make unsaturated)

196
Q

Principal fatty acid precursors in ruminant mammary gland

A

Acetate and much smaller amounts of a-hydroxybutyrate (remember acetate is the precursor of milk fat! So we have to keep forage levels high)

197
Q

Where are fatty acids made

A

The microsome

198
Q

Overview of fatty acid synthesis

A

Made from acetyl CoA (from carbs, amino acids, or fats)

The carboxyl end of one acetate (from acetyl-CoA) joins the methyl end of another. This repeats to eventually make palmitate, and then other fatty acids are made by modifications of palmitate

199
Q

Procedures to generate other fatty acids from palmitate?

A

Elongation, desaturation, and hydroxylation

200
Q

TG degradation

A

Either oxidized in place or transported to other tissues as albumin-fatty acid complexes for oxidation there

Liver, heart, and resting skeletal muscles all rely on fatty acid oxidation for energy (ATP)

201
Q

Where does the glycerol from TG degredation go?

A

Liver, where it can either be used for energy or converted to glucose

202
Q

Fates of acetyl CoA

A
Entry into TCA
Synthesis of long chain fatty acids
Acetylation reactions
Steroid synthesis
Ketone body formation
203
Q

Exercise increases ____ levels

A

HDL, which is poorly associated with heart disease (LDL is)

204
Q

Eating beef promotes more ____ than _____

A

HDL than LDL

205
Q

What percent of the population will benefit from diet alterations?

A

2%

206
Q

Supplementation with _____ Will prevent arteriosclerosis?

A

Vitamin E, it’s an antioxidant so it prevents the oxidation of lipids while they’re circulating in the blood, which prevents arteries from being damaged and therefore makes them less susceptible to plaque lay down

207
Q

Ketogenesis

A

Continuous process, normally the ketones are removed rapidly from the blood by muscle

They are used to supply energy

208
Q

Normally fat constitutes about __ of the wet weight of the liver, but it can be up to ____ or more in pathological conditions

A

5%, 30%

209
Q

Causes of fatty livers

A

High fat or high cholesterol diet
Increased liver lipogenesis caused by excessive carb or excess intake of certain B vitamins
Increased mobilization of lipids from adipose tissue caused by diabetes
Starvation
Hypoglycemia
Increased hormone output (growth hormone, adrenal corticotrophic hormone, adrenal corticosteroids)
Decreased transport of lipids from the liver to other tissues caused by deficiencies in choline, pantothenic acid, inositol, protein, or certain amino acids (met and thr)

210
Q

Atherosclerosis

A

NOT ARTERIOSCLEROSIS

Characterized by progressive degenerative changes in the blood vessels and heart of humans and animals

Associated with high serum cholesterol concentration (saturated fats raise it and eating cholesterol)

LDL increases risk, HDL reduces it

211
Q

Average American (M+P)/S is _____

A

0.5:1

As this ratio goes up, less plasma cholesterol

212
Q

Omega-3’s do what to the clotting time of blood?

A

Increase it, so it protects against the atherogenic process