Test 2 Material Flashcards
What are examples of glycerol based lipids?
-Phospholipids
-Triglycerides
What is fatty acids melting point determined by?
-chain length
-saturation
Low melting point fatty acids are more ___ than high melting point fatty acids.
Unsaturated
Fatty acids with higher melting points have ___ chain lengths than low melting point fatty acids.
Longer
What characterizes a fatty acid with a cis double bond?
Bent Chain
Rumen microbes modify the fatty acid composition of dietary fatty acids through a process called….
Biohydrogenation
Following absorption by enterocytes of the small intestine, where are the absorbed lipids released to?
Lymph into lacteals
Fatty acids are stored in the body as ___ in cells called ___.
-Triglycerides
-Adipocytes
What are the two essential fatty acids in animals?
-Linoleic acid
-Linolenic acid
What makes Linoleic acid and Linolenic acids essential?
They include bonds beyond carbon 9 where animals cannot add them.
Explain why fatty acids in animals have even numbers of carbons in their fatty acyl chains.
-Fatty acids are synthesized from acetyl-CoA.
-Acetyl-CoA is 2 carbons in length so when fatty acids are synthesized from them, they end up with even numbers of carbons, 2 at a time.
How does epinephrine regulate lipolysis to release stored fatty acids from adipose tissue?
Epinephrine circulates during times in which the animal needs to act or exert energy, therefore lipolysis is stimulated to provide energy for the animal.
How does insulin regulate lipolysis to release stored fatty acids from adipose tissue?
Insulin circulates when there is excess glucose circulating, therefore lipolysis is inhibited because the animal already has sufficient energy availability.
Vitamins generally act as what for metabolism of other nutrients?
Catalysts
What are examples of fat-soluble vitamins?
-Vitamin A
-Vitamin D
-Vitamin E
-Vitamin K
What minerals does Vitamin D regulate?
-Phosphorus
-Calcium
What describes Vitamin E?
-It is incorporated into membranes
-It prevents the formation of peroxides
-It is found within forages and cereal grains
Night blindness, epithelial tissue defects, and abnormal bone development of fetuses and neonates are all symptoms of a deficiency in which of these vitamins?
Vitamin A
Parathyroid hormone ___ calcium absorption, and calcitonin ___ calcium absorption.
-Promotes
-Reduces
What is, the vitamin, Pantothenic acid’s active cofactor?
Coenzyme A
What is, the vitamin, Niacin’s active cofactor?
NAD
What is, the vitamin, Thiamin’s active cofactor?
TPP
What is, the vitamin, Riboflavin’s active cofactor?
FAD
Selenium is a mineral that is incorporated into proteins as _____. An example enzyme that includes selenium is ____.
-Selenocysteine
-Glutathione peroxidase
List the components of the net Energy System in order.
- Gross energy
- Digestible energy
- Metabolizable energy
- Net energy
What are products of the citric acid cycle?
-GTP
-FADH2
-Carbon dioxide
-NADH+H+
What supplies the energy gradient necessary to phosphorylate ADP to ATP?
H+
If you wanted to measure the total energy in an organic material, you could use a ___. This device ___ the sample in the presence of ___ to release the energy.
-bomb calorimeter
-ignites
-oxygen
If you want to calculate digestible energy, what should you subtract from gross energy?
Fecal energy
If you want to calculate metabolizable energy, then you should subtract what from digestible energy?
-Urinary energy
-Gaseous energy
If you want to calculate net energy, what should you subtract from metabolizable energy?
-Heat increment
-Heat of fermentation
If you wish to calculate metabolic body weight, you can calculate it by raising the animal’s body to the ___ power.
0.75
Lipids are absorbed by the small intestine in what form?
Mixed micelles
Pancreatic lipase hydrolyzes triglycerides into ___ fatty acids and ___.
-2
-monglyceride
Microbial lipase hydrolyzes triglycerides into ___ fatty acids and ____.
-3
-glycerol
Body fat and body water are ___ related with each other.
Inversely
Newborn animals have a ____ proportion of body weight as body water compared to older animals due to body composition changes with age.
Greater
What are potential ways animals lose water?
-breath
-sweat
-urine
-feces
If a dog weighs 19.5 kg, what is the dog’s metabolic body weight in kg?
9.28 kg
What fatty acids are required in the diets of animals?
-Linoleic acid
-Linolenic acid
If a feed is 14.5% crude protein on a dry matter basis and it is 87% dry matter, what is the protein concentration on an as fed basis?
12.62%
Which cell type stores triglycerides?
Adipocytes
A ration calls for 712 lb of dry matter for a ration ingredient. If that ingredient is 35% dry matter, how many pounds of the ingredient should be weighed out and fed?
2034 lb
What regulates lipolysis in adipocytes?
-glucagon
-norepinephrine
-epinephrine
-insulin
What is involved in lipogenesis?
-ATP
-Acetyl-CoA
-NADPH
-CO2
A bomb calorimeter is used to…
Measure the total energy content of a sample.
Fasting heat production represents an animal’s ___. You can measure the fasting heat production of an animal using a ____.
-Basal metabolic rate
-Respiration chamber
Propionate is the major gluconeogenic substrate of ruminants. For propionate to be converted into glucose during gluconeogenesis, methylmalonyl CoA has to be converted to succinyl CoA. However, this process is compromised when there is a lack of:
Cobalamin (Vitamin B12)
Which of the following can have its dietary requirement offset by the dietary addition of Selenium:
Vitamin E
What are examples of macro minerials?
-Sulfur
-Magnesium
-Potassium
Calcium and Phosphorus are related to various functions of the body, and tracking the dietary ratio of these minerals is important to keep these functions. A good ratio of Ca/P for most animals is:
2:1
Microorganisms in the rumen can synthesize vitamin ___ when ruminants are fed ___.
-B12
-Cobalt
Select which of the following is a precursor required for FAD and FMN:
Riboflavin (B2)
Discuss what the direct products of
beta-oxidation are, how much is produced per cycle, and where the products are utilized to generate ATP.
-B-oxidation produces 1 NADH2, 1FADH2, and 1 acetyl-CoA per cycle.
-The last cycle produces 2 acetyl-CoA (1 point). FADH2 and NADH go to the electron transport chain to produce ATP.
-Acetyl-CoA goes into the TCA cycle to produce ATP and more NADH and FADH2 that feed into the electron transport chain.
Discuss two differences in ruminant and non-ruminant lipid digestion.
-Lipids are hydrolyzed by microbial lipase in ruminants and breaks down triglycerides into 3 free fatty acids
-Whereas pancreatic lipase in non-ruminants produces 2 free fatty acids.
-Biohydrogenation occurs in the rumen and saturates a majority of the free fatty acids.
-Saturation of fatty acids occurs post-absorption in non-ruminants (1pt).
The volume of water animals drink is influenced by many factors. What can influence water intake?
-Feed water
-High temperatures
-Palatability
-Physiological state
-anticipated availability
How does feed water influence water intake?
consuming water in feeds decreases drinking because water is being consumed in feed that meets requirements
How does high temperatures influence water intake?
increase intake: greater losses from the body from insensible losses or sweating
How does palatability influence water intake?
decreasing water quality or palatability reduces intake because animal is resistant to drinking
How does physiological state influence water intake?
lactation increases intake because output is increased raising requirements
How does anticipated availability influence water intake?
scarcity of infrequent availability increases intake because animals anticipate need when water is infrequently available
Water is available to animals in different ways including metabolic water, also known as water of oxidation. Explain what this is.
Metabolic water is water produced through the oxidation of nutrients.
Water is available to animals in different ways including metabolic water, also known as water of oxidation. Explain how it supplies water to animals.
-As lipids, carbohydrates, and amino acids are oxidized, the hydrogens are combined with oxygen to produce water that is endogenously produced in the body from these nutrients.
-Lipids produced the greatest yield of water per mass of nutrient oxidized.
Water is available to animals in different ways including metabolic water, also known as water of oxidation. In what cases or situations is it important?
A number of cases where animals require metabolic water are possible including hibernation, long, non-stop migrations, and living in arid environments with limited water availability.
What are the inputs and outputs of the citric acid (AKA Krebs or tricarboxylic acid) cycle?
-Acetyl-CoA is the input and can be derived from acetyl-CoA from pyruvate or beta oxidation of fatty acids or ruminally produced acetate.
-Carbon dioxide is one output along with NADH+H, FADH2, and GTP.
Explain the energy produced from the citric acid cycle and its products.
-GTP is used to produce ATP from ADP.
-The NADH and FADH2 enter the electron transport chain.
-The hydrogens (protons and electrons) are used to produce a gradient that provides the energy for oxidative phosphorylation of ADP to ATP.
-The NADH and FADH2 are used to produce ATP
- 3 ATP per NADH and 2 ATP from FADH2.
What are the components of the net energy system?
Gross, digestible, metabolizable, and net energy are the components of the NE system.
What is gross energy?
Gross energy is the total energy of a feed measured by bomb calorimetry.
How is digestible energy calculated?
-DE is GE minus fecal energy.
-Fecal energy is the energy contained in the feces: the gross or feed energy that is not digested.
How is metabolic energy calculated?
-ME is DE minus urinary energy and gaseous energy.
-Urinary energy is the energy lost in urine and gaseous energy is the combustible gaseous energy lost largely from fermentation.
How is net energy calculated?
-NE is ME minus heat increment and heat of fermentation.
-Heat increment is the heat of digestion, the difference in heat production between a fed animal and a fasted one.
-Heat of fermentation is heat produced during the fermentation of feeds in animals that actively ferment feeds.
Vitamin D can be synthesized in the animal body. However, synthesis and activation involve a complex process in different tissues. Describe in detail how that occurs.
-It is converted to 7-dehydrocholesterol in the skin upon exposure to ultraviolet irradiation
-It is transported from the skin to the liver, where it is hydroxylated to form 25-hydroxycholecalciferol
-Transported through the blood to the kidneys, where it is further hydroxylated to form 1,25-hydroxycholecalciferol, also called calcitriol, which is the most metabolically active form of vitamin D.
The body has a strictly controlled physiological regulation called homeostasis—that is, maintenance of a steady state of circulating blood plasma calcium. Describe in detail how blood calcium levels are regulated in the organism.
-When Blood Ca is low PTH is released
-Stimulates synthesis of active Vitamin D, increasing Ca absorption from the intestine
-Stimulates osteoclasts, increasing Ca mobilization from bone and increases Ca resorption in the kidney, decreasing Ca excretion in urine, and increasing Ca in blood.
-When Blood Ca is high Calcitonin is released
-Decreasing Ca mobilization from bones, inhibiting osteoblasts and Ca reabsorption from kidneys
A farmer had to keep his herd of sheep inside the barn for a longer time than usual due to unfavorable climate conditions that prevented pasture recovery. During this time animals were fed a “winter diet” consisting of grass hay, wheat grain, soybean meal, and a mineral/vitamin supplement. The supplement used in the winter diet was the same as the one used when the animals were grazing, and its inclusion dose was kept the same to avoid problems with an excess of certain minerals (e.g., Manganese and Iron) that were present in high concentration in the supplement and close to the limit for sheep. After six months, the farmer started noticing abnormalities in the herd, such as abortions, a drastic drop in the conception rate, malformed lambs (mostly with incompletely developed eyes), and symptoms of night blindness in adult sheep. Based on your knowledge, explain the possible cause of these problems (justify) and suggest a solution.
-Long time to start the symptoms (vitamin A is stored in the body)
-Problems with reproduction
-Problems related to vision
-Absence of fresh forages
-a source of carotenoids - vitamin A precursor
-Treatment: injectable vitamin A and inclusion of fresh forage in the diet
What are the common characteristics of lipids?
-insoluble in water
-energy dense
-storage form of energy
What are the nutritionally important types of lipids?
-simple glyerolipids: triglycerides
-compound glyerolipids: phospholipids and glycolipids
What are the types of fatty acid structures?
-Glycerol based
-Non-glycerol based
What are examples of glycerol based fatty acids?
-triglycerides
-phospholipids
-glycolipids
What source can linolenic and linoleic acid come from?
Plants
What are chylomicrons?
-lipid export from the enterocytes
-composed of lipid rich particles from things like triglycerides
-go into the lymph
Describe the absorption, packaging, and export of digested lipids from the small intestine.
-Absorption: fatty acids in mixed micelles are absorbed across the plasma membrane and re-esterified
-Packaging: Chylomicrons
Describe the parts pf essential fatty acid metabolism that result in downstream products.
-Desaturation: adds double bonds
-Elongation: makes fatty acids longer
Describe the sources of substrate for fatty acid synthesis.
-Substrate: Acetyl-Coa
-In non-ruminants get from citric acid cycle
-In ruminants get from rumen
Describe the overview process of fatty acid synthesis.
-condensation: lose CO2
-Reduction: add H to close bonds
-Dehydration
-Reduction
How are fatty acids stored?
As triglycerides in adipocytes of adipose tissue
Describe mobilization of fatty acids from adipocytes.
-energy deficit
-lipolysis hydrolysis triglycerides and release the products into the blood
-produces glycerol and free fatty acids
-lipolysis carried out by hormone sensitive lipase
List the cobalt and vitamin B12 deficiency symptoms.
-neurological disorders
-wasting disease (rumen): propionate metabolism (glucose)
What is the relationship between cobalt and vitamin B12?
-Vitamin B12 contains cobalt
-ruminants use microbial synthesis on Co to receive
-Co needs to be effected by the rumen
Describe the functions and relationship of vitamin E and selenium.
-Vitamin E prevents the formation of peroxides
-selenium is in an enzyme that destroys hydrogen peroxide: glutathione peroxidase
-partners as antioxidants
Describe the sources of Vitamin A.
-fat soluble sources like fish oils, milk fat, egg yolk, and liver
-from concentrates like green forages
What are the functions of vitamin A?
-precursor for formation of rhodopsin (visual pigment in retina)
-night vision
-embryonic cell differentiation
-retinoic acid interacts with a cellular protein receptor to turn on and off genes
Explain the relationship of body water in terms of composition.
-As body fat increases, body water decreases
-body fat has very little water
-water is associated with lean tissue
List sources of water loss.
-urine
-feces
-lungs
-skin
-sweet
What gives the most metabolic water?
Fat
What are examples of insensible water loss?
-skin
-lungs
-NOT sweat
What is the inputs, products, and purpose of the citric acid cycle?
-Inputs: Acetyl-Coa
-Products: 3 NADH+H+, 1 FADH2, 1 GTP, (byproduct CO2)
-Purpose: energy
Link products of citric acid cycle to electron transport and oxidative phosphorylation to generate energy.
-NADH and FADH2 go into electron transport chain
-Oxidative phosphorylation gets ADP from the citric acid cycle
Describe GE and its meaning.
-Total amount of energy in feed
-measure heat to know how much energy
Explain the losses when moving through the components of the net energy system.
-GE to DE lose FE
-DE to ME lose UE and GE
-ME to NE lose heat
Describe the relation of body size and heat production
-Body size and heat production are related by metabolic body weight
-BW^0.75
-scale energy requirements
