Nutrition Exam - Final

When analyzing feeds, some components are determined by difference. If we calculate: 100% - %Ash - % Crude fiber - % Ether Extract - (%N - 6.25) - %Water, we get

%NFE (nitrogen free extract)

Describe iron absorption

- Active transport across mucosal cell - Can be stored within cell - Regulation occurs at the point of uptake into the blood stream

Difference between cofactor and a coenzyme

A coenzyme is an organic compound (usually involves a vitamin) that catalyzes a reaction. A co-factor is an inorganic ion that catalyzes a reaction.

NAD and FAD are coenzymes involved in oxidation-reduction reactions involved in the TCA cycle. What is the primary benefit to the body as a result of these reactions?

ATP is produced

Matching: Perosis

Mn

Mitochondrial isomers of SOD need which element as a cofactor:

Mn

Perosis is a nutrient deficiency disease involving

Mn deficiency in poultry

A deficiency of which combination of nutrients would increase requirements for Vitamin E and Se?

Mn, Zn, and Cu

Which statement best describes the advantage for conversion of pyruvate to lactate under conditions of limited oxygen concentrations in muscle tissue?1

NAD can be regenerated to allow continued generation of energy within muscle

Which statement best describes the advantage for conversion of pyruvate to lactate under conditions of limited oxygen concentrations in muscle tissue?2

NADH is oxidized to allow continued generation of energy within muscle

Nutrients that primarily function as electrolytes include

Na, K, and Cl

Mammals can use tryptophan in the synthesis of which vitamin:

Niacin

Pellagra, a nutrient deficiency disease in humans, was initially associated with two vitamins but later shown to be cured by supplements of which vitamin:

Niacin

Which vitamins are directly involved as coenzymes in substrate reactions within the TCA cycle?

Niacin and riboflavin

Which group of vitamins are most likely deficient in ingredients commonly fed to swine so supplemental sources must be added to the diet

Niacin, B12, and riboflavin, and pantothenic acid

As a structural component of hemoglobin, Fe contributes:

Oxidation states that affect oxygen and carbon dioxide binding to heme proteins

Which nutrient is never found in elemental form in nature, but as a compound with another element, because in free-form spontaneous combustion occurs

P

Acetyl Coenzyme A is most closely associated with:

Pantothenic Acid

Matching: animal protein growth factor

Vitamin B12

Which nutrient deficiency would be evident first in an adult consuming a vegetarian diet?

Vitamin B12

Which nutrient was known as the animal protein growth factor before it was identified?

Vitamin B12

Which statement best describes the relationship between niacin and NAD. NAD is the:

coenzyme formed from dietary sources of niacin

Dietary sources of B vitamins are converted into complex derivatives before becoming functional in metabolic pathways. These complex derivatives are

coenzymes

Dietary sources of B vitamins are converted into complex derivatives before becoming functional in metabolic pathways. These complex derivatives are broadly classified as:

coenzymes

Differences in the intracellular and extracellular concentrations of sodium and potassium are maintained by:

active transport

The major biochemical reactions requiring biotin involve:

additions of carboxyl groups to substrates

The major biochemical reactions requiring folic acid are reactions involving:

additions of methyl groups to substrates

In addition to structural support, the skeletal tissue provides

all of the below: a source of buffer to help maintain acid-base balance, a source of Ca to help maintain soft-tissue Ca homeostasis, a storage site for excess trace elements

Vitamin K is involved in gamma carboxylation to

alter glutamate residues and affect Ca binding

The relationship between nutraceuticals and vitamins can best be described as: Nutraceuticals are...

compounds present in foods with health benefits

Early signs of vitamin K deficiency would likely be detected as

an increased in time required for blood coagulation

Absorption of vitamin B12 requires

an intestinal "intrinsic factor" that decreases with age

The only known function for iodine involves a role as a structural component of a hormone involved in regulation of ___

basal metabolic rate

Transport of reducing equivalents among organic compounds thru the electron transport chain results in

consumption of ADP AND generation of ATP

Primary result of a thiamin deficiency

beriberi

Matching: bound by avidin in raw eggs

biotin

Matching: cofactor for carboxylases

biotin

Growing animals fed diets with a marginal deficiency of P would first show deficiency symptoms as a reduction in

bone mass (with P deficiency, body wt gain is compromised first and then bone. With Ca deficiency, bone is compromised first)

The interrelationships between Vitamin E and Se could best be described as:

both are antioxidants, but function in different cellular components

Classification of choline as a vitamin is questionable since choline

can be synthesized by the body

Vitamin E functions as a scavenger of free radicals. This function occurs primarily in

cell membranes

Sodium is the major extracellular cation, which anion balances sodium in extracellular fluids?

chloride

Which one of the following fatty acids is considered an essential nutrient:

cis-9, cis-12 linoleic acid

In mammals the percentage of body water:

decreases with body fat content

For which of the following feeds is digestible energy content (or TDN) likely to be lower when fed to a pig rather than if it is fed to a steer? a. mineral supplement b. corn oil c. refined barley starch d. cane sugar e. pelleted oat straw

e. pelleted oat straw

The major biochemical reactions requiring riboflavin involve:

electron transfer and generation of ATP

Cu functions as a co-factor for lysyl oxidase. Loss of function in this enzyme causes:

failure to modify amino acids needed to form crosslinks in the protein strands

Peanut butter cookies are excellent sources of niacin

false

T/F: Body iron status regulation occurs at uptake into intestinal mucosa

false

Absorption of iron involves regulation by:

ferroportin, a protein requiring Cu

Spina bifida results from failure of neural tube closure in the early fetus as a result of

folate deficiencies

Identified as a "cure" for pernicious anemia

folic acid

Patients with pernicious anemia can best be cured with supplements of:

folic acid

Which vitamin primarily functions in transfer of carbon atoms between substrates:

folic acid

The US food supply (primarily flour) is now supplemented with __ to prevent birth defects

folic acid as this vitamin is unlikely to create a toxicity

Distinct chemical properties used to identify niacin and riboflavin as separate nutrients involved:

heat stability

Distinction between roles of niacin and riboflavin as separate nutrients involved which chemical property?

heat stability

Toxic substance formed during methionine metabolism

homocysteine

Which animal species is the most susceptible to iodine toxicity

horses

Ideal dietary ratios of Ca:P differs from ratios in bone because concentrations of Ca and P:

in diets are altered because of differences in bioabailability of P

Substances in feed ingredients identified as nutraceuticals involve

ingredients with medical benefits

What are the 3 phases of free radical induced peroxidative damage?

initiation, propagation, termination

A deficiency of vitamin C causes scurvy. Which statement best describes the link between scurvy and hydroxyproline when vitamin C is deficient? Hydroxyproline:

is not formed so collagen fibrils are de-stabilized, allowing a loss of membrane integrity

Conversion of precursors to the most active form of vitamin D occurs in

kidneys

Consider an animal that eats dietary fat, converts this to body fat, and the mobilizes the stored body fat to form plasma non-esterified fatty acids (NEFA). The LAST enzyme in this process is:

lipoprotein lipase

Zinc absorption is regulated by:

metallothionein proteins in the mucosa cells

Which group of amino acids includes only essential amino acids?

methionine, lysine, and tryptophan

Generally ruminant animals do not require additions of B vitamins to diets because

microbes synthesize the vitamins which are absorbed in the lower tract

Generally ruminant animals do not require additions of B vitamins to diets because:

microbes synthesize the vitamins which are absorbed in the lower tract

Tocopherols describe compounds with vitamin E activity. naturally occurring tocopherols exist as:

multiple derivatives, all of which contribute variable vitamin E activity

Phytochemicals are:

naturally occurring compounds in plant foods that favorably alter mammalian metabolism

Matching: 4 D's

niacin

Matching: black tongue

niacin

Matching: nicotinamide adenine dinucleotide

niacin

Matching: pellagra

niacin

Vitamin needed to form nicotinamide adenine dinucleotide

niacin

In addition to a role in methyl transfer for conversion of homocysteine to methionine, vitamin B12 is involved in:

nucleic acid synthesis

Matching: acetyl coenzyme A

pantothenic acid

Matching: coenzyme A

pantothenic acid

Matching: goose stepping

pantothenic acid

Primary result of niacin deficiency

pellagra

Substances found in edible fruit and vegetable ingested daily

phytochemicals

Phytic phosphorous is a source of P from:

plants that is not available to monogastrics

Which one of the following schemes is a good generic representation of digestion of starch or true protein in a non-ruminant in the proper sequence:

polymer -> monomer -> portal vein ->liver -> heart -> tissues

General term to describe sources of reactive oxygen species (ROS)

pro-oxidants

Which one of the following fermentation products, produced in the rumen or large intestine, is absorbed and then used by the host animal as a precursor to synthesize blood glucose:

propionic acid

Superoxide dimutase is an enzyme that

reacts with oxygen radicals

Body stores of trace elements are typically regulated by

regulation of absorption in the small intestine

Cation and anion balance in the body is regulated mainly by:

renal responses

Cu affects Fe status via:

requirement of Cu as a cofactor for ferroportin protein

Zinc deficiencies

result in skin lesions called parakeratosis

Matching: flavin adenine dinucleotide

riboflavin

Vitamin E and Se are involved in reactions with oxygen radicals. Which statement best describes the interrelationships between these nutrients:

roles complementary so a deficiency of one nutrient is compensated by the other

Iodized ___ is the most common way humans receive iodine in their diet

salt

Incidence of milk fever in early lactation of animals is associated with a deficiency of:

serum Ca but ample dietary Ca concentrations

Water absorption occurs mainly in the:

small intestine and colon

Primary result of a folate deficiency

spin bifida

Pick the single lettered choice that contains two items that have essentially identical amounts of gross energy per pound

starch and cellulose

The functional role of Se involves:

substitution of Se for sulfur in cysteine residues of proteins

Within an animal's thermal neutral zone each of the following stays constant as ambient temperature changes EXCEPT for:

the animal's insulation capacity (resistance to heat transfer)

The pancreatic and bile ducts open into the lumen of the intestinal tract in:

the duodenum

Folate deficiencies that induce a birth defect know as spina bifida are more likely to occur in:

the early trimester of pregnancy before closure of the neural tube

Each of the following is part of the ruminant stomach EXCEPT for:

the pro-ventriculus

Thiamin deficiencies were first identified in animals consuming polished vs whole rice. Differences between the rice sources are explained as:

the seed coat (pericarp) fraction contains most of the thiamin, so removal induced a deficiency

If the "best" way to meet all B vitamin requirements is to consume a variety of feed ingredients, why are production animals fed diets with supplemental sources of B vitamins?

the variety of alternate feed ingredients needed to meet B vitamins are more expensive than fewer, less costly, ingredients supplemented with the necessary B vitamins

Matching: beriberi

thiamin

The only functional role for iodine in the body involves iodine's role as a structural component of:

thyroxine

Goitrogens are compounds that block metabolic function involved in:

thyroxine synthesis

B vitamins function in metabolism of dietary carbohydrates, fat, and proteins to:

transfer chemical energy into forms that can be used in other pathways in cells

Niacin and riboflavin are involved in oxidation-reduction reactions. The net benefit of these reactions in oxidative phosphorylation involves:

transfer of chemical energy from nutrients to ATP

Water movement in and out of the GI tract is controlled by

transport of Na, K, and Cl

In order for proteolysis to occur, inactive proteolytic enzymes secreted by the pancreas must first be converted to the active form. Indicate the pancreatic enzyme that is responsible for activation of the other pancreatic enzymes in this process:

trypsin

Nutrient requirements for common production animals and companion animals are:

uncertain in many cases due to experimental designs used to establish requirements

Worldwide distribution of Se deficiency is:

unequal because Se is deficient in some soil types

Regulation of body iron status occurs at:

uptake into the blood stream

Se excretion occurs via:

urine, feces, and lungs

Substances in feed ingredients identified as nutraceuticals involve ingredients:

with medical benefits

Zinc absorption is dependent on:

Metallothioein proteins in the mucosa cells for uptake into the intestinal lumen

The role of choline as a vitamin is questionable, but choline does function as a:

Methyl donor

An alternate pathway to deplete homocysteine involves use of methyl groups from

Betaine and choline

Why pellagra was prevalent in southeast US but not in Mexico in people consuming similar diets:

Both groups consumed corn as major source of food. In Mexico the corn was soaked in a alkaline solution before cooking. The alkaline treatment released the bound niacin in corn, making niacin available to humans.

Under conditions of limited water supplies, which food source would you select to reduce chances of water deficiency?

Fat

Anemia is most often associated with a deficiency of

Fe

Matching: Anemia

Fe

Matching: oxidative damage

Fe

Main storage form of Fe

Ferritin

Iron absorption is regulated by

Ferroportin proteins in the mucosa cells

Homocysteine is a toxic substrate that accumulates if which nutrients are deficient?

Folate and B6

Matching: Methyl transfers

Folic acid

Matching: spina bifidia

Folic acid

Which pair of B vitamins are most closely linked with an accumulation of homocysteine?

Folic acid and B12

In the early 1900's pellagra was associated with consumption of predominately corn-based diets in the southeastern US, but people consuming similar diets in Mexico did not develop pellagara because:

Food preparation methods common in Mexico improved nutrient availability in corn

The more common target tissues for 1,25(OH)2 vitamin D include

GI tract, bone, and kidneys

Explain the difference between Goiter and Graves disease:

Goiter is related to excess or deficient Iodine. Graves disease is an autoimmune disease that is not related to Iodine levels.

Matching: Basal metabolic rate

I

Matching: Goiter

I

Matching: binds to tyrosine residues

I

What are the end products of the coenzymes NAD and FAD and what are the benefits of these end products? Identify vitamins associated with each coenzyme

ATP is the ultimate end product (NADH and FADH, immediate), ATP is used as energy for the cell, Niacin is associated with NAD and riboflavin is associated with FAD

Fe is typically bound to proteins in the body, but free (ionized) Fe

Acts to initiate the formation of free radicals

What is the definition of a nutrient?

An element or compound required for a defined physiological process. Cannot be synthesized by the body at all or if it is, not in amounts sufficient for health. Must be obtained from a dietary source.

A deficiency of which nutrient is more likely to occur in strict vegetarians?

B12

An "intrinsic factor" which decreases with age in humans is required for absorption of:

B12

deficiency of ___ is most likely to occur in strict vegetarians

B12

A deficiency of what two vitamins are involved in the "Folate Trap?" Which steps of methyl transfers are each of these vitamins involved in?

B12 and B6. B12 involved in homocysteine to methionine reaction. B6 involved in THF to 5,10-methylene THF reaction.

A carnivore must synthesize much of its blood glucose from amino acids. All of the following steps are important in this overall process EXCEPT for:

Conversion of non-essential amino acids to essential amino acids

Anemia is most often associated with a Fe deficiency, but may also be induced by a deficiency of:

Cu

Matching: Collagen crosslinks

Cu

Matching: cystolic superoxide dimutase

Cu

Which nutrient deficiency is most likely to affect hair or feather color?

Cu

Concentrations of Na and K in physiological fluids are:

Dramatically different, K is mostly intracellular; Na is mostly extracellular

T/F: Folate B12 and choline are primary sources of methyl groups

F

T/F: Folate supplements are not recommended to pregnant women

F

T/F: One cycle of pyruvate through the TCA cycle generates 15 moles of ATP

F

T/F: feeds with antioxidant activity are not needed in production livestock diets

F

T/F: only excess iodine will cause Goiter

F

T/F: Foods with antioxidant activity are helpful for humans because of their potential to reduce chronic health concerns, but are not needed in production livestock diets

False

T/F: Metallothionein proteins are proteins involved in trace metal transport in circulation

False

T/F: geographical distribution of Se deficiency is equal because Se is uniformly distributed in all soil types

False

Compared with fat soluble vitamins, B vitamins are MORE/LESS likely to result in a deficiency if deleted from diets of ruminant animals for a short time period

LESS

Compared with fat soluble vitamins, B vitamins are MORE/LESS likely to result in a toxicity if overfed

LESS

The Cori cycle describes:

Lactate production in the muscle is converted to glucose after transport to the liver

Four of the following five choices contain two different names for the same compound. Which does NOT name a single compound?

Lactose and lactic acid

Compared with fat soluble vitamins, B vitamins are MORE/LESS likely to result in a deficiency if deleted from diets of monogastric animals for a short period of time

MORE

Free radicals involve unpaired electrons that propagate in compounds such as fatty acids. The damaged FAs cause concern because:

Membrane integrity is disrupted and cellular funciton compromised

Which animal species would be more susceptible to Mn deficiency?

Poultry

Which combination of hormones are most closely linked to regulation of cation-anion balance?

Renin, aldosterone, and angiosensin

If one of the following nutrients were instantly removed from the diet, which nutrient would produce deficiencies symptoms first? (iodine, vitamin e, riboflavin, phsohorus)

Riboflavin

Matching: Curled toe paralysis

Riboflavin

Microbial protein synthesis in the rumen provides an important source of dietary protein. Each of the following is an important input for microbial protein synthesis EXCEPT for:

Rumen undegraded protein

Attempts to identify requirements for vitamin E may be affected by dietary levels of:

Se

Glutathione peroxidase is most closely associated with

Se

Matching: Keshan's disease

Se

Matching: Mullberry heart disease

Se

Matching: White muscle disease/ mulberry heart disease

Se

Matching: blind staggers

Se

The only nutrient regulated by the FDA is

Se

Which nutrient is most likely to create a toxicity if overfed

Se

Deficiencies of these trace minerals are often associated with deficiencies in the soils that supply feed ingredients to the animals

Se and I

Which combination of nutrients are all associated with a decrease in free radicals

Se, Mn, Zn, and Cu

The liver is important for each of the following functions EXCEPT for:

Synthesis of digestive enzymes secreted into the small intestine (Is: synthesis of bile salts secreted into the small intestine, synthesis of urea from excess nitrogen and absorbed ammonia, synthesis of ketones and blood glucose, detoxification of toxic compounds absorbed from the digestive tract)

T/F: B12 is not involved in oxidation-reduction reactions

T

T/F: B12 is required to convert homocysteine to methionine

T

T/F: Goitrogens are compounds that block functions involved in throxine synthesis

T

T/F: Mammals can use tryptophan in synthesis of niacin

T

T/F: Microbes within the rumen have the ability to synthesis B vitamins

T

T/F: nutraceuticals are isolated compounds present in whole foods with health benefits

T

T/F: toxicity due to B vitamins is less likely than a toxicity of fat soluble vitamins

T

Most active form of thyroxine

T3

Compound with vitamin E activity

Tocopherol

Metallothionein proteins are proteins involved in:

Trace metal ABSORPTION

Nutrient metabolism of dietary carbohydrates, fat, and proteins involve numerous chemical reactions. B vitamins are involved in many of these steps and function to:

Transfer chemical energy to forms that can be used in other pathways in cells

T/F: Cu deficiencies can decrease Fe absorption and cause anemia

True

T/F: Parakeratosis in swine is caused by a Zn deficiency

True

Se excretion is unique among trace elements with multiple routs for excretion. Excretion of Se occurs via:

Urine, feces, and lungs

Matching: Transamination

Vitamin B6

Nutrients that primarily function as free radical scavengers include

Vitamin E and Se

Oxidative metabolism generates peroxides that can be harmful to mammalian cells, which group of nutrients are directly involved in protecting cells from oxygen radicals?

Vitamin E and Se

Thermoregulation involves the ability to store heat and lose heat. Which nutrient is not directly involved in thermoregulation?

Water

Cofactor for carbonic anhydrase:

Zn

Cystolic isomers of SOD need which element as a cofactor:

Zn

Which statement most correctly describes the cause of Goiter?

a lack of thyroxine (T3) feedback leads to thyroid gland hypertrophy (NOT HYPOTROPHY)

The functional role of Se involves (not subst):

a role as a structural component for proteins with antioxidant activity

The relationship between cobalt and vitamin B12 can best be described by which statement? Cobalt is:

a structural part of the vitamin B12 molecule

Zinc absorption is regulated by:

a transporter on the serosal membrane that controls uptake into blood

One cycle of substrates through the TCA cycle generates

a. 12 moles of ATP c. 3 moles of NADH and 1 mole of FADH e. Both A and C are correct <<<<<<

Which of the following has the lowest total 'herd' requirement for Net Energy (cows are not changing body energy): a. A herd of 10 Holstein cows, each weighing 1500 pounds, each cow producing 100 pounds daily of milk that is 5% lactose, 3% protein and 3% fat. b. A herd of 10 Holstein cows, each weighing 1500 pounds, each cow producing 100 pounds daily of milk that is 5% lactose, 3% protein and 5% fat. c. A herd of 20 Jersey cows, each weighing 750 pounds, each cow producing 50 pounds daily of milk that is 5% lactose, 3% protein and 3% fat. d. A herd of 20 Jersey cows, each weighing 750 pounds, each cow producing 50 pounds daily of milk that is 5% lactose, 3% protein and 5% fat.

a. A herd of 10 Holstein cows, each weighing 1500 pounds, each cow producing 100 pounds daily of milk that is 5% lactose, 3% protein and 3% fat. Has the least fat, but still produces 1000 lbs milk with the least # of cows (more efficient)

Biotin functions as a coenzyme for carboxylase enzymes. Deficiency symptoms observed in biotin deficient animals are related to the role of carboxylase enzymes in synthesis of:

a. fatty acids b. chrondrotin sulfate d. a & b

Goiter is caused by:

a. iodine deficiency b. iodine excess c. auto immune disease d. all of the above <<<<<

Reactive oxygen species (ROS) are

a. produced in the body during normal metabolism b. supplied by environment inputs in addition to food c. only of concern if the body has a deficiency of antioxidants d. all of the above<<<<

Reactive oxygen species are:

a. produced in the body during normal metabolism b. supplied by environmental inputs in addition to food c. only of concern if the body has a deficiency of antioxidants d. all of the above <<<<<

Important steps in synthesizing glucose from amino acids:

a. proteolysis of dietary protein b. removal of the N from amino acids by transamination d. synthesis of urea to remove excess N e. transport of absorbed amino acids to the liver

Requires pantothenic acid for synthesis

acetyl coenzyme A

The vitamin identified as the actual nutrient supplied by the "animal protein growth factor" was:

vitamin B12

Matching: pyridoxamine

vitamin B6

Matching: scurvy

vitamin C

Which vitamins is involved in the conversion of proline to hydroxyproline?

vitamin C

Which combination of nutrients are involved in the conversion of proline to hydroxyproline?

vitamin C and Fe

Which nutrient is most directly involved in terminating the propagation of free radicals?

vitamin E (not: niacin, riboflavin, vitamin C)

Metabolic water describes

water produced by nutrient catabolism