Exam 3 Flashcards
1
Q
1st fate of carbohydrates
A
energy now
- glycolysis: glucose to 2 pyruvate
- TCA Cycle: acetyl-coa to reducing agents
- ETC: reducing equivalents to ATP (36)
2
Q
2nd fate of carbohydrates
A
short term energy storage
- glycogen (glycogenesis)
- glucogenolysis
3
Q
3rd fate of carbohydrates
A
long term energy storage
- lipogenesis
- FA from acetyl-coa from glycolysis and extra step
4
Q
Where does the electron transport chain occur?
A
in the mitochondrion of all cells
- some mitochondrion’s are more efficient than others
5
Q
What goes into the electron transport chain?
A
FADH2 and NADH
6
Q
What goes out of the electron transport chain?
A
ATP
7
Q
What is the biggest limitation of the electron transport chain?
A
oxygen (O2)
- electron transport chain must happen in aerobic conditions
8
Q
What is produced during anaerobic respiration?
A
lactic acid
9
Q
How is glucose moved around the body? What can it be used for once in the cell?
A
- glucose is moved through blood
- once in the cell it can be used to make ATP
10
Q
When does brown adipose fat occur?
A
there is extra mitochondria that have uncoupling proteins meaning that the product is heat rather than ATP
11
Q
What age group is more likely to have brown adipose fat?
A
babies because they need the extra heat (internal heater) to stay warm after birth
12
Q
define glycogenesis
A
glycogen synthesis
13
Q
When does glycogenesis occur?
A
high blood glucose (in a fed state)
14
Q
Why does glycogenesis occur?
A
when an animal is in a high blood glucose state, you will make glycogen to store the glucose for short term energy storage
15
Q
define glycogenolysis
A
glycogen breakdown
16
Q
When does glycogenolysis occur?
A
low blood glucose
17
Q
Why does glycogenolysis occur?
A
when animals have low blood glucose concentration they begin to break down glycogen to increase glucose in the blood
18
Q
How are triglycerides formed?
A
- carbohydrates make acetyl-coa
- through lipogenesis acetyl-coa is turned into fatty acids
- fatty acids then form ester bonds with a glycerol (esterification) backbone to become a triglyceride
19
Q
What are fats (adipose)/tirglycerides used for in the body?
A
long term energy storage
20
Q
How much more energy does fats have?
A
2.25 times more energy per gram
21
Q
glycolysis: in and out
A
- in: glucose (6 carbons)
- out: 2 pyruvate (3 C each)
22
Q
TCA Cycle: in and out
A
- in: acetyl-coa
- out: reducing equivalents (FADH2 and NADH)
23
Q
Electron Transport Chain: in and out
A
- in: reducing equivalents
- out: ATP (in higher amounts)
24
Q
gluconeogenesis: in and out
A
- in: pyruvate
- out: glucose
25
What are VFAs made into?
pyruvate that can be used in gluconeogenosis
26
glycogenesis: in and out
- in: glucose
- out: glycogen
27
glycogenolysis: in and out
- in: glycogen
- out: glucose
28
lipogenesis: in and out
- in: acetyl-coa
- out: fatty acids
29
CHO feedstuffs types
- energy
- coproducts
- forages
- proteins have some CHO as well
30
high starch feedstuffs
- cereal grains
- co-products
31
examples of cereal grains
- corn
- barley
- oats
- wheat
- milo
- rye
- triticale
- hominy
- millet
32
examples of co-products
- potatoes = roots
- bread waste = what flour
- bakery waste = wheat flour
33
Why do we base ourselves in high starch feedstuffs?
- they are consumable by humans and animals
- easy to grow
34
What is the most common energy feed that is fed to livestock?
cereal grains
35
What is the most common cereal grain fed to livestock?
corn
36
Why do we feed starches?
- high starches have high energy
- all animals have enzymes to break down starches
37
cereal grains: protein
variable in quality and quantity
- not a protein feed (low amounts)
- not idea AA profile for the animals eating them
38
cereal grains: fat
1 to 6% fats (oils, typically unsaturated)
39
cereal grains: P and Ca
more phosphorus than calcium
- phosphorus is a waste concern
- costs more money
40
What is phytase? Why is it added to feed?
- an enzyme that breaks down phosphorus
- added to the feed to help non ruminants (swine and poultry) to help break it down
41
cereal grains: vitamins
- low in vitamin A, D, and b complex
- moderate vitamin E
(poor source of vitamins)
42
Why are animals not just fed cereal grains?
animals are not just fed cereal grains because it is not a good source of everything that is needed in the diet
43
What type of corn is fed?
yellow, dent corn
44
What pigment is in yellow corn? What vitamin?
- pigment = cryptoxanthin
- vitamin A
45
corn: starch
- 72% starch
- endosperm
46
corn: CP
- variable, about 8-11%
- low in lysine and trypsin
- 46% RDP so 55% RUP
47
What is zein?
the protein found in corn
48
Why should we know the protein content of corn?
corn can have variable protein content. When using a lot of corn, the amount of protein can become very significant. So understanding what is being put into the diet is important.
49
What is pellagra?
a disease caused by niacin (b vitamin) deficiency
- corn is low in niacin
50
Are all AA profiles similar or different in corn kernels?
similar
51
Why are seeds often fed to animals?
seeds are a good source of energy
52
corn anatomy: dent
at the top, where there is a "dent" in the kernel
53
corn anatomy: endosperm
starch (high amount)
- the white portion inside the kernel
54
Why does corn have an endosperm?
provides an energy source for the seed to germinate into a plant
55
corn anatomy: pericap
fiber coating
56
Why does the seed have a pericap?
protection for the seed
57
Why can the pericap cause issues for animals and feeding?
the fiber coating is difficult for animals to break down because we cannot digest fiber, so somehow we have to break the fiber coating (chew, crack)
58
corn anatomy: germ
protein portion
59
corn anatomy: tip cap
fiber
60
Why do we feed so much corn?
1. high energy/high starch content
2. grown well in the US
3. good source of food and other products for humans
4. corn prices affect other feed costs like hay
61
all cereal grains vs corn: protein
corn < all other cereal grains
62
all cereal grains vs corn: energy
corn > all other cereal grains (except hard red wheat)
63
Who can we feed whole shelled corn to?
ruminants
64
Why do we feed whole shelled corn?
it costs less even though they don't get as much out of it
65
define "processing corn"
breaking up the fiber coating
66
examples of processed corn
- ground corn
- steam flaked corn
- high moisture corn
- corn silage
67
Who is fed ground corn?
non ruminants (swine and poultry)
68
Why is ground corn not often fed to ruminants?
ground corn can be digested very fast and in ruminants it can be digested too fast and may cause sub acute acidosis
69
Who is high moisture corn fed to?
ruminants only
70
Who is corn silage fed to?
ruminants only
71
Why is corn silage only fed to ruminants?
it has a high fiber content because you are ensiling the entire plant
72
examples of high sugar (disaccharide) feedstuffs
- molasses - sucrose (beet, cane, citrus, starch, wood)
- concentrated separator byproduct
- milk byproducts (whey and lactose)
73
What is the most common high sugar feedstuff?
cane molasses
74
Why is cane molasses commonly used?
- conditioner
- palatability
- pellet binder
- feed additive vehicles
- liquid supplement base
75
What does conditioner mean for a feedstuff?
it decreases dust
76
What does palatability mean for a feedstuff?
tastes better, the animal is more likely to want to eat it
77
What is whey?
a milk by-product
- can be from the liquid when making cheese
78
In what forms can whey be in?
- fresh (4-5% DM - 95% H2O)
- condensed (40-50% DM - 50% H2O)
- dehydrated (>90% DM)
79
What is the most common form of whey used? Why?
dehydrated because it is much easier to transport
80
nutrient composition of whey: protein
- 10-13%
- casein (main protein in milk)
81
nutrient composition of whey: lactose
- 55-70%
- used in: mammal diet, milk replacer, nursery pig diet
82
nutrient composition of whey: minerals
- high in calcium
- lots of macro minerals
83
2 Classes of High Fiber Feedstuffs
1. forages
2. high fiber co-products
84
define forage
- high (if not all) fiber
- grazed: pasture, range, browse
- harvested: hay, haulage, silage
85
How does hays DM content affect storage?
- DM = 80-90%
- a good shelf life
86
How does haylage/silage DM content affect storage?
- DM = 35-50%
- needs to be wrapped up
87
define high fiber co-products
- fibrous coatings from grains/seeds
- co-products (because coating is removed
- structural carb (protects the plant
88
Why feed and animal more fiber?
make the animal feel and look more full
89
define NDF
Neutral Detergent Fiber
- an indicator of all the fiber of the feed and leads to fill
90
define ADF
Acid Detergent Fiber
- less digestible
91
In diets do we feed more NDF or ADF?
NDF > ADF
92
What are some examples of NDF contents?
- lignin (not digestible)
- cellulose (semi digestible)
- hemicellulose (very digestible)
93
What are some examples of ADF contents?
- lignin (not digestible)
- cellulose (semi digestible)
94
As NDF increases an animal will eat:
LESS
95
As ADF increases digestibility:
DECREASES
96
Why would an animal eat less when NDF is increased?
- dense product
- in digestive system longer
97
More NDF = _______ intake
lower
98
Less NDF = ________ intake
higher
99
define bran
outer covering of grain kernel
100
define hull
outer covering of grain kernel/seed
101
define midd
some grain kernels, endosperm
102
define mill run
bran, minds, sometimes starch
103
define shorts
bran, germ, starch, tailings
104
define screenings
cleanings of grains/seeds
105
define pulp
residue after processing, extracting, juicing
106
What co-products would you add to get extra protein and starch?
midds, mill run, shorts
107
Wheat co-products
- wheat
- what bran
- wheat midds (most common)
108
What are more common attributes in co-products?
protein and fiber
109
nutrient composition of co-products: fiber
- high in soluble fibers
- meaning digestive fibers (lower in lignin)
110
nutrient composition of co-products: CP
- can be moderate
- AA profile is poor for animals
111
nutrient composition of co-products: minerals
- often higher in Ca
- can be high P and magnesium
- usually higher in trace minerals
112
loose soy hulls vs pelleted soy hulls
- loose = more easily blow away
- pelleted = less likely to blow away
113
nutrition of soy hulls
- some protein
- high in fiber (low in lignin)
- high energy value
(liked by animals)
114
cottonseed hulls vs pelleted
- cottonseed hulls = fluffy
- pelleted = more palatable
115
nutrition of cottonseed hulls
- low in protein
- higher fiber than soyhulls
- high in lignin
- low energy
116
What are cottonseed hulls used for?
add bulk, make animals feel and look bigger
117
fibrous co-product feeding considerations
- bulky/fluffy
- low density (usually pellet)
- variable palatability
- variable quality
118
How can we increase palatability in co-products?
- pellet
- add molasses
119
Why should we be concerned about the variable quality in co-products?
- the nutrient composition is variable because it is just the leftovers
- can have negative compounds
120
Which species is often not given co-products?
horses because they could not handle negative compounds
121
Which species gets fed the most fiber co-products?
ruminants
122
What is supplemented when feeding fibrous co-products to cow-calf and grazing animals?
supplement vitamins E + P
123
Why would we feed fibrous co-products to feed lots and conventional dairies?
decrease the chances of the animals getting sub acute acidosis, feed fibers to increase ph
124
Why feed fibrous co-products to ruminants in general?
- low cost
- rumen microbes can take care of most of the negative compounds
125
When are nonruminants fed fibrous co-products: swine
gestating sows and gut health
126
When are nonruminants fed fibrous co-products: pets (especially dogs)
- weight management (dog feels full)
- improved fecal consistency
***higher quality control
127
When are nonruminants fed fibrous co-products: poultry
used less, higher quality (less fiber)
128
How many carbons in a short chained FA?
2-8 (made from fermentation)
129
How many carbons are in a long chained FA
12-20 carbons
130
What are long chained FA used for?
storage in energy in plants/animals or parts of cell membranes/walls
131
What are saturated FA?
there are no carbon carbon double bonds
132
What are unsaturated FA?
there is one or more carbon carbon double bonds
133
What does omega "3" fatty acid mean?
the number following omega (so in this case 3) is where the carbon carbon double bond is
134
define monounsaturated
one carbon carbon double bond
135
define polyunsaturated
greater than one carbon carbon double bond
136
What does the abbreviation C12:0 mean?
there are 12 carbons : 0 double bonds
137
What are the chemical properties of a saturated FA?
- straight chains
- solid at room temperature
138
Why are saturated FA solid at room temperature?
the FA chains are straight so they can pack together
139
What are the chemical properties of unsaturated FA?
- bend in the chain
- oils are room temperature
140
Why are unsaturated FA oils at room temperature?
there are kinks in the FA chain so they cannot pack together closely
141
long carbon chain and more saturated: melting point?
higher melting point
142
unsaturated FA: melting point?
really low
143
define iodine number
indicated oxidative stability
144
define oxidative stability
- the opportunity of lipids to oxidize
- more oxidation when there are greater C=C bonds
- oxidation causes off flavors and odors
145
the more unsaturated bonds: oxidative stability?
lower oxidative stability
146
Lipid Types
- simple lipids
- compound lipids
- sterols
- etc.
147
What lipid types are most commonly found in feed?
simple lipids and compound lipids
148
What is the most common fat found in feed?
triglycerides
149
What are phospholipids and glycolipids used for?
found in plant or animal cell membranes
150
define esters
the type of bond between FA and alcohol
(FA and glycerol backbone)
151
What lipids are common in glycerol and FA?
glycerol and fatty acids (triglycerides - 3FA)
152
What lipids make up waxes (made from plants)?
other alcohol and fatty acids (2 FA)
153
examples of steroid hormones
- testosterone
- progesterone
154
Why are sterols higher in animal tissues?
because we make them
155
Why do we need cholesterol?
cholesterol is needed to make steroid hormones
156
What are the most important lipids in animal nutrition?
- monoglyceride
- diglyceride
- triglyceride
- phospholipid
157
Why is lipid digestion different from CHO and protein digestion?
lipids are insoluble in water
158
What is the main process in lipid digestion and absorption?
making lipids miscible (soluble) in water
159
Where are bile salts produced? Where are they secreted?
- produced: liver
- stored: gallbladder
- secreted: duodenum of small intestine
160
emulsification by bile salts
the bile salts go between the large glob of fat and the salts can interact with the fat breaking the large glob into small droplets of fat
161
Where is pancreatic lipase released?
the duodenum
162
what does pancreatic lipase do after emulsification?
pancreatic lipase can remove FA (1 and 3) from the triglyceride (creating a monoglyceride)
163
mixed micelle organization
a sphere with a polar (hydrophilic) exterior and a non polar (hydrophobic) interior
164
What is the mixed micelle composed of?
- bile salts
- free FA
- monoglycerides
- fat soluble vitamins (ADEK)
165
Why do lipids need to form into mixed micelles?
so that they can be with digesta and blood (watery substances)
166
How do mixed micelles enter the enterocyte?
1. fusion between the micelle and the lipid bilayer (because the enterocyte is made of phospholipids)
- simple diffusion
2. bile salts are absorbed further down the gi tract
- protein transporters
167
What happens to FA when inside the enterocyte?
monoglycerides and 2 fatty acids make a triglyceride, then a protein is added to make a chylomicron
(fat soluble vitamins and cholesterol are incorporated)
168
Why are proteins added onto the triglyceride?
proteins keep lipids from becoming large globs and it helps to overcome some insolubility in the blood so it can travel in the bloodstream
169
Where are chylomicrons absorbed into the bloodstream?
- 20% directly into the blood
- 80% into the lymphatic system
170
4 Classes of Lipoproteins
- chylomicron
- VLDL
- LDL
- HDL
171
define VLDL
- very low density lipoprotein
- high percent triglycerides
172
define LDL
- low density lipoprotein
- high percent cholesterol
173
define HDL
- high density lipoprotein
- higher protein
174
5 Functions of Lipids
1. supply essential FA
2. absorption of fat-soluble vitamins
3. energy
4. cell membranes
5. biosignaling
175
Why are lipids REQUIRED in the diet?
- make essential FA
- absorption of fat-soluble vitamins (ADEK)
176
essential FAs
- linoleic acid
- linolenic acid
- arachidonic acid (carnivores only)
177
Why is arachidonic acid only essential for carnivores?
carnivores do not have the enzymes to transfer linolenic acid to arachidonic acid (all other animals do)
178
name the fatty acid: C18:2
linoleic acid
179
name the fatty acid: C18:3
linolenic acid
180
name the fatty acid: C20:4
arachidonic acid
181
Why will you often not get essential fatty acids from ruminant fats?
ruminant fats are often biohydrogenized (saturated) by ruminal microbes and the essential fatty acids are all unsaturated fats
182
Why do we need essential fatty acids in our bodies?
- important component of cell membrane structure
- eicosanoid production
183
3 Classes of Eicosanoid
1. prostoglandins
2. thromboxanes
3. leukotrienes
184
What are eicosanoids used for in the body?
they help with the normal function of the animal
- reproduction
- blood
- etc.
185
What essential FA is responsible for making eicosanoids?
arachidonic acid
186
What are deficiency symptoms of essential fatty acids?
- scaly skin
- skin lesions
- decreased growth
- reproductive failure
- edema
- hemorrhage
187
Why is it important that we have lipids in our diet for carrying lipid-soluble vitamins?
- lipid soluble vitamins (ADEK) look similar to lipids so they are insoluble in water
- without dietary fats we have a decreased absorption of these vitamins
188
Why are lipids known for having a high energy value?
- lipids have 2.25 times more energy per gram than CHO and proteins
- high digestibility in animals
189
Why can animals get so much energy from lipids?
high digestibility:
- ruminants: microbes cannot ferment it
- able to break it down ourselves and use it
190
Where are lipids stored?
- adipose
- gi tract (omental and mesenteric)
191
What are the cellular membranes made up of?
phospholipids (create a bilayer)
192
What is the function of the cellular membrane?
semi-permeable, lets select things in and out
193
What is a phospholipid made up of?
- 1 hydrophilic head
- 2 hydrophobic tails
194
How are lipids used for biosignaling?
through sterols and cholesterol products
195
Why do we need to have cholesterol in the body?
needed to make important products within the body used for biosignaling
196
products of sterols and cholesterol
- steroid hormones
- vitamin D precursor
- bile acids
197
What fatty acids can be catabolized?
1. dietary fat
2. adipose
198
Steps to TG Catabolism
1. lipolysis - take TG and break into 3 FA
2. beta oxidation - FA turns to acetyl-coa
3. TCA Cycle - acetyl-coa to NADH, FADH2
4. ETC - NADH, FADH2 to ATP
199
define beta oxidation
- breaking down fatty acids into acetyl-coa
- cutting between every two carbons
200
define non-esterified fatty acids or NEFA
there are no ester bonds, the fatty acids are no longer attached to a backbone
201
define esterification
forming ester bonds to make a triglyceride
202
Where is energy derived in fatty acid catabolism?
- beta oxidation
- electron transport chain
203
What are the uses for acetyl-coa?
1. TCA Cycle (ETC)
2. ketogenesis
3. cholesterologenesis
4. lipogenesis
204
What is a more rare use for acetyl-coa?
lipogenesis because after beta oxidation there is only a fatty acid
205
How much ATP is used to activate a fatty acid for beta oxidation?
2 ATP
206
How much ATP is released for every acetyl-coa division?
5 ATP
207
How many ATP are produced if one acetyl-coa enters the TCA cycle?
1 ATP (3NADH, 1 FADH2) So 12
208
When does fatty acid biosynthesis occur?
1. excess carbon from CHO and c-skeletons of AA in need of being stored
2. the diet does not have enough fat to perform important functions
209
Steps of TG Biosynthesis
1. acetyl-coa (lipogenesis) to a fatty acid
2. fatty acid (esterification) to a triglyceride
3. a triglyceride is then stored
210
How are fatty acids synthesized?
by adding two carbons (acetyl-coa) back at a time
211
What organs and tissues are involved with lipids?
- liver
- adipose tissue
- small intestine
- muscle
212
Where is the central place for lipid metabolism?
liver
213
What processes occur in the liver with lipids?
- glycolysis
- beta oxidation
- esterification
- lipolysis
214
Where is fat primarily stored?
adipose tissue
215
What processes occur in adipose tissue with lipids?
- glycolysis
- esterification
- lipolysis
216
Which organ do we get triglycerides from the diet?
small intestine
217
Where can fat also be stored?
muscle
218
What processes occur in muscle with lipids?
- beta oxidation
- lipolysis
- esterification
219
define ketogenesis
the formation of ketones from acetyl-coa
220
Why are ketone bodies used?
they are used as an energy source when there is low blood glucose
221
What are common ketone bodies?
- acetone
- beta hydroxy butyrate (BHBA)
222
When does ketogenesis occur?
- blood glucose is low
- there is more dietary lipids available
223
In what animals are ketones more common?
- carnivores
- early lactation dairy cows
- late gestation litter bearing ruminants (goats and sheep)
224
define ketosis
an overload of ketones in the body
225
When does ketosis occur?
- available CHO is low
- energy requirements are high
- increased mobilization from adipose
226
Why are some animals more susceptible to ketosis?
they have high energy requirements and low blood glucose (early lactation dairy cows and late gestation litter bearing ruminants)
227
define pregnancy toxemia
ketosis, overload of ketones
228
What issues can ketosis cause?
- brain fog
- more tired
- acetone breath
229
Why do we need fat?
1. increase energetic density of the ration
2. there are essential FA
3. benefits of liquid feeds
230
How do we add fat into the diet?
1. add a fat only source
2. choose higher fat feedstuffs
231
Why is feeding ruminants fats different than nonruminants?
1. microbes saturate the fat
2. fat changes to the microbes (decrease in digestibility)
232
Why would having too much fat in the diet decrease digestibility in ruminants?
microbes cannot ferment FA so they would have a much harder time digesting the feeds
233
Why would you add fat to the diet?
1. physiologically
2. feed intake decreases
3. milk replacements
234
adding fat to the diet: physiologically
- lactation (dairy animals)
- laying hens
235
adding fat to the diet: feed intake decreases
- increase the energy of the feed
- nursery animals
236
adding fat to the diet: milk replacers
milk has a lot of energy from fat (milk=4% fat)
237
What are the fats and oils that can be fed?
1. animal fats
2. vegetable fats
3. blended products
238
examples of animal fats
- prime tallow
- leachable fancy tallow
- choice white grease
- poultry grease
239
examples of vegetable plants
- refining vegetable oils
- acidulated vegetable soapstock
- lecithin
240
examples of blended products
- yellow grease
- vegetable-animal blend
241
Are animal fats more saturated or unsaturated?
saturated
242
Are vegetable fats more saturated or unsaturated?
unsaturated
243
Why are feeding fats expensive?
because human costs have increased, fats and oil costs have increased
244
What is the benefit to feeding oils?
- conditioner (decrease dust)
- pelleting
- help grease the feed product and machinery
245
What are the parts of an amino acid?
- amine (NH2)
- central carbon
- carboxyl group (COOH)
- r group/side chain
246
What are the classifications of amino acids?
- neutral, polar
- neutral, non polar
- basic (higher ph)
- acidic (lower ph)
247
Other Ways to Classify AA
- R-groups (cyclic, sulfur containing)
- essential
- nonessential
248
What are the 10 essential AA?
- phenylalanine (phe)
- valine (val)
- threonine (the)
- tryptophan (try)
- isoleucine (ile)
- methionine (met)
- histidine (his)
- arginine (arg)
- leucine (leu)
- lysine (lys)
249
What are the 10 nonessential AA?
- alanine (ala)
- aspartate (asp)
- asparagine (asn)
- cysteine (cys)
- glutamate (glu)
- glycine (gly)
- proline (pro)
- serine (ser)
- tyrosine (tyr)
250
define peptide bonds
the bond between amino acids in the primary structure of protein
251
define dipeptide
2 AA
252
define tripeptide
3 AA
253
4 Levels of the Protein Structure
1. primary protein structure
2. secondary protein structure
3. tertiary protein structure
4. quaternary protein structure
254
define primary protein structure
- long string of amino acids (peptides)
- determined by translation of RNA to protein
255
define secondary protein structure
- beta pleated sheets
- alpha helix
256
define tertiary protein structure
- polypeptide folds into a 3D structure with all the beta pleated sheets and alpha helix structures
- helps to expose important regions and important AA
257
What is the tertiary protein structure based on?
the interaction between r groups
258
define quaternary structure
- 2 polypeptides come together (not bonded)
- many times proteins work best when they work with another protein
259
What is the nutritional importance of protein structure?
1. digestion of the protein (undo the 4 levels of structure)
2. making proteins (taking AA from the diet and use to build proteins for the body)
260
Digestion of Proteins
fully formed protein to denature (HCl and pepsin) and digest to AA, dipeptide and tripeptide (enzyme)
261
What do protein transporters absorb?
- single AA
- dipeptide
- tripeptide
262
define assimilation of proteins
making proteins again
263
Absorbed AA Functions
1. synthesize protein (based on translation)
2. leftover AA for energy (c-skeleton)
3. small molecules synthesized by a single AA
264
What is the central dogma?
DNA is transcribes to RNA which is translated into DNA
265
What are RNA codons used for?
codons code for specific amino acids
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What happens when the specific AA that is being transcribed for is not in the body?
translation cannot occur
267
How can AA be converted to small molecules?
single AA or dipeptide that forms into a compound to help the animal function
268
Examples of Small Molecules formed out of AA
- arginine --> nitric oxide
- glutamate --> GABA
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What are the two ways that AA can enter the TCA Cycle?
1. ketogenic
2. glucogenic
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What has to happen to the AA before it can provide energy?
deaminate (remove NH3 leaving the c-skeleton)
271
How do proteins get their function?
based off the interactions of the R-Groups in the AA profile
272
What AA are used in protein synthesis?
all 20 (common) amino acids
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list the protein functions
1. structural (collagen, muscle, keratin)
2. blood proteins
3. enzymes
4. hormones
5. biosignaling
6. immune function
7. complexed with other nutrients
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essential amino acids can be made but not enough, this has to do with:
1. species
2. age
3. diet
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define AA interconversion/transamination
ability to swap or move anime groups from one amino acid to another
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Can non-ruminants synthesize AA?
NO
277
Can we store AA?
NO, but we can store carbon
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define AA degradation
deamination
- c-skeleton (energy - used or stored)
- NH3 (excreted)
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When do we make proteins?
only when DNA tells us to, when DNA is transcribed into RNA
280
define the urea cycle
turning NH3 (ammonia) into urea
281
Why would the body change ammonia to urea?
NH3 is a neurotoxin and bad for the body while urea is safe and can be circulated through the body
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In what organelle does the urea cycle occur?
mitochondria
283
In what organs does the urea cycle occur?
- kidneys
- liver
- small intestine
284
Where does urea go after the conversion in the kidneys?
excreted in urine
285
Where does urea go after the conversion in the liver and small intestine?
the blood
286
In what animals can nitrogen recycling occur in?
ruminants ONLY
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Where do ruminants get their sources of NH3?
- themselves
- rumen microbes
288
After a microbe deaminates an AA, and does not use NH3 in AA synthesis, where does the NH3 go and used for?
NH3 goes into the blood and converted to urea, then can be recycled back into the rumen
289
define nitrogen recycling
urea in the blood can go back to the rumen
290
Where does urea go in a ruminant?
1. rumen epithelium (blood to rumen)
2. salivary glands (will eventually end up in rumen)
291
How is urea used once back in the rumen?
microbes can cleave urea and use the nitrogen for AA synthesis
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Why do ruminants do nitrogen recycling?
to decrease waste of nitrogen from the diet
293
When do ruminants use nitrogen recycling?
1. helpful for animals that have low nitrogen/CP intake (decrease of nutrient availability)
2. only have to feed supplement a couple times a week
294
plant proteins
- poor AA profile
- some heating issues: increased RDP, decreased RUP
295
animal proteins
- better AA profile
- heating: decreased RDP, increased RUP
296
How does RDP affect AA profile?
microbes are able to degrade the proteins and turn it into microbial crude protein for the animal, making a better AA profile
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How does RDP affect AA profile?
RUP is degraded by the animals, it is metabolizable protein, the animal gets all the nutrients from it
298
Why do we feed protein to the animal?
provides nonessential amino acids
299
Why do we feed AA supplements to animals?
once absorbed, amino acids can provide energy or protein or small molecules
300
Why do we feed proteins and supplement AA?
so that the animal can get everything it needs
301
Where do AA come from?
1. feed protein
2. MCP (ruminants only)
3. endogenous proteins (normal turnover and starvation)
302
What is the first limiting protein?
the lowest AA in the diet (under the requirements)
303
What affects the first limiting AA?
- species
- diet
- physiological state
304
What is the most common protein feed for livestock?
oilseed meals
305
Why do we feed corn and soybean meal together?
SBM is high in protein and low in methionine. Corn is low in protein and has moderate methionine.
