Chapter 6 study questions
The specific sequence of amino acids in a polypeptide chain is determined by a. The types of food proteins that a person consumes. b. DNA found in the nucleus of cells. c. GI tract peptidases. d. Random interactions between free amino acids in the cytoplasm of cells.
b. DNA found in the nucleus of cells
Vegan vegetarians may not get enough of which nutrient(s)? a. Iron and zinc b. Vitamin B12 c. Calcium and vitamin D d. All these nutrients could be low
d. all of these nutrients could be low
Protein complementation is a technique which: a. increases the biological value of a protein. b. increases the nitrogen content of dietary protein sources. c. minimizes nitrogen loss in the urine. d. combines proteins from different sources so that essential amino acids requirements are met.
d. combines proteins from different sources so that essential amino acids requirements are met.
amino acids cannot be synthesized by the body are called _____ amino acids a. hydrolyzed b. conditionally essential c. nonessential d. essential
d. essential
Which nutrient is found in plant protein foods but not in animal protein foods? a. iron b. zinc c. calcium d. fiber
d. fiber
what end product of deamination is released into the urine? a. nitrosamine b. uric acid c. ammonia d. urea
c. ammonia
how many amino acids are essential? a. 8 b. 9 c. 11 d. 20
b. 9 (there are 9 essential and 11 nonessential)
Which of the following statements is true regarding an amino acid pool? a. amino acids in the pool can be metabolized for energy b. all types of proteins are synthesized at a constant rate c. structural proteins have a quick rate of turnover. d. only dietary protein is added to the amino acid pool.
a, amino acids in the pool can be metabolized for energy
transamination refers to: a. a mechanism for synthesizing non-essential amino acids b. the removal of an amino group from an amino cid to from ammonia. c. removal of an acid group from an amino acid d. formation of a peptide bond
a. a mechanism for synthesizing non-essential amino acids
Which of the following is a physical characteristic associated with Kwashiorkor? a. Bloated abdomen b. Excess sweating c. Tall stature d. Hypertrophic (enlarged) leg muscles
a. bloated abdomen
To estimate protein requirements, you must know a person's: a. body weight. b. urinary ammonia output. c. height. d. all of these would be required.
a. body weight
The synthesis of glucose from certain amino acids involves: a. deamination. b. transcription. c. translation. d. transamination.
a. deamination
Protein digestion continues in the_____ of the ____intestine. a. duodenum-small b. ileum- large c. duodenum-large d. jejunum- small
a. duodenum-small
why is the shape of a protein important? a. it determines the protein's function b. it can sustain changes in environmental conditions c. it can be synthesized by the body d. it can be denatured.
a. it determines the protein's function
what is true about protein energy malnutrition? a. it is characterized by wasting and susceptibility to infection. b. it results from adequate protein but insufficient carbohydrate intake. c. it results from the breakdown of body fat. d. it occurs most often in breast-fed infants.
a. it is characterized by wasting and susceptibility to infection
which of the following foods contains little to no protein? a. margarine b. kidney beans c. skim milk d. wheat
a. margarine
how does protein quality affect needs? a. more plant protein is needed to supply enough of all the essential amino acids b. animal proteins as compared to plant proteins are considered low quality c. plant proteins are easier to digest and absorb. d. all the essential amino acids can be supplied by a single plant protein source.
a. more plant protein is needed to supply enough of all the essential amino acids
Which structure(s) is/are involved in protein translation? a. Ribosome and tRNA b. Nucleus and nucleosome c. Mitochondria d. Plasma membrane and trans-Golgi
a. ribosome and tRNA
Which nutrient(s) found in animal protein foods is not found in plant protein foods? a. Saturated fat b. B vitamins c. Phytochemicals d. None of these nutrients are found in plant protein foods
a. saturated fat
Kwashiorkor is best characterized by: a. severe protein deficiency in young children. b. increased susceptibility to food allergies in adults. c. misshapen (sickle-shaped) red blood cells. d. the inability to digest proteins from soy and other plant proteins.
a. severe protein deficiency in young children
Transamination refers to: a. the transfer of an amino group from one amino acid to a carbon-containing molecule to form a nonessential amino acid. b. the removal of the amine group from an amino acid. c. the interaction of amino acid side chains important for protein folding. d. the formation of a peptide bond between adjacent amino acids.
a. the transfer of an amino group from one amino acid to a carbon-containing molecule to form a nonessential amino acid
Which of the following is NOT an example of a protein complementation? a. tofu crumbles and spinach b. peanut butter and jelly sandwich c. trail mix (soybeans and nuts) d. lentil and rice soup
a. tofu crumbles and spinach
The process of ___________ involves copying the DNA code from the gene to a molecule of mRNA. a. transcription. b. nuclear shuttling. c. transamination. d. translation.
a. transcription
As long as vegetarians consume high quality proteins in the diet, there is little risk to develop a protein deficiency a. true b. false
a. true
Protein consumption is associated with stimulation of immune response in humans a. true b. false
a. true
a limiting amino acid is an essential amino acid available in the lowest concentration in relation tot he body's needs a. true b. false
a. true
the acceptable macronutrient range for protein is ___ % of total kilocalories a. <10 b. 10-35 c. 35-50 d. >50
b. 10-35
Hemoglobin is an example of: a. a defense protein. b. a transport protein. c. an enzyme. d. an immune protein (antibody)
b. a transport protein
which term best describes all of the amino acids in body tissues an fluids that are available for use by the body? a, deamination b. amino acid pool c. translation d. protein turnover
b. amino acid pool
End products of protein digestion include: a. monosaccharides and glucose b. amino acids, dipeptides, and tripeptides c. glycerides and fatty acids d. polypeptides and tripeptides
b. amino acids, dipeptides, and tripeptides
An amino group can combine with hydrogen to form _____ which is toxic. a. nitrogen b. ammonia c. hydroxyl d. urea
b. ammonia
How are protein needs met through complementation? a. the body must produce the amino acids to complement the protein needed. b. combining two plant proteins, rice and beans, will provide the essential amino acids needed c. a protein of animal origin must complement the plant source of protein. d. any plant proteins can be combined to provide the essential amino acids needed.
b. combining two plant proteins, rice and beans, will provide the essential amino acids needed.
Kwashiorkor is a form of protein energy malnutrition in which a deficiency of energy in the diet causes severe body wasting a. true b. false
b. false
A person eats large amounts of protein sources in the diet but yet ends up with an amino acid deficiency. How could this occurrence happen? a. limited competition exists between amino acids b. Increased absorption of competing amino acids that use the same transport system. c. all diets should include protein supplementation to prevent this type of situation from occurring d. structural differences in amino acids lead to clinical deficiencies as a result of competition.
b. increased absorption of competing amino acids that use the same transport system
______a stomach enzyme, initiates the break-down process by fragmenting proteins into peptides. a. Protease b. Pepsin c. Lipase d. Rennin
b. pepsin
why must some amino acids be consumed in the diet? a. they are more important than others b. they cannot be synthesized by the body. c. they are more susceptible to environmental insults. d. they have a more complex structure than others.
b. they cannot be synthesized by the body
What is true about the function of proteins in the body? a. they provide an efficient energy source for the body b. they transport substances through the body c. they delay metabolic reactions d. they function effectively in a wide range of pH levels.
b. they transport substances throughout the body.
The waste product resulting from the deamination of a protein is: a. ketone bodies. b.urea. c. lactate. d. CO2.
b. urea
A pattern of food intake that eliminates all animal products is called: a. lacto-ovo vegetarian. b. vegan vegetarian. c. phyto vegetarian. d. pesco vegetarian
b. vegan vegetarian
which nutrient deficiencies can be a problem for vegetarians, particularly vegans? a. omega-3 fatty acids, folate, selenium b. vitamin B12, calcium, iron c. protein, vitamin A, vitamin B6 d. zinc, fiber, vitamin C
b. vitamin B12, calcium, iron
_____, dipeptides, and tripeptides are absorbed at the mucosal cells of the small intestine a. Polyglycerides b. Polypeptides c. Amino acids d. Proteins
c. amino acids
Unlike carbohydrates and triglycerides, _____are not stored. a. monosaccharides and glucose b.acetic acids and proteins c. amino acids and proteins d. glycerides and fatty acids
c. amino acids and proteins
high-quality protein is found in: a. animal proteins only b. plant proteins only c. animal and soy proteins d. none of these choices
c. animal and soy proteins
food allergies: a. cause skin symptoms only b. are rare in infants c. are triggered by incompletely digested proteins d. are worse the first time the offending food is eaten
c. are triggered by incompletely digested proteins
Amino acids found in the amino acid pool of the body: a. can be used to generate energy 9 kilocalories per gram. b. exist in a static environment c. are used to synthesize both protein and non-protein molecules. d. are provided for solely by dietary intake
c. are used to synthesize both protein an non-protein molecules
protein differs form carbohydrate and lipid in that protein: a. does not provide the body with a source of energy b. is classified as an inorganic molecule c contains the element nitrogen d. is not considered to be an essential nutrient
c. contains the element nitrogen
a. What is a benefit of a vegetarian diet? a. it is low in fiber b. it is high in calories c. it is low in saturated fat d. it is high in iron and zinc
c. it is low in saturated fats
Adverse reactions including flushing, headache, rapid heartbeat, chest pain and weakness have been reported after the consumption of: a. phenylalanine. b. isoflavones. c. monosodium glutamate. d. dipotassium phosphate.
c. monosodium glutamate
where does protein digestion begin? a. mouth b. small intestines c. stomach d. liver
c. stomach
which of the following is NOT true about amino acids? a. they synthesize glucose. b. the can be converted to fat c. they are comprised of three elements only - carbon, hydrogen, and oxygen d. they are energy-yielding
c. they are comprised of three elements only - carbon, hydrogen, and oxygen
all of the following are true of food allergies except: a. they are triggered when a protein is absorbed without being completely digested. b. proteins from milk, eggs, peanuts, trees nuts, wheat, soy, fish, and shellfish are common causes c. they are not a serious concern d. they may trigger anaphylaxis
c. they are not a serious concern
__________________ are at increased risk of not getting adequate vitamin B12 in their diet. a. Lacto-ovo vegetarians b. Trained athletes c. Vegan vegetarians d. Pregnant and lactating women
c. vegan vegetarians
The AMDR for protein intake is _______% of energy intake. a. 20-35 b. 45-65 c. 30-45 d. 10-35
d. 10-35
Proteins regulate which of the following body processes? a. Acid-base balance b. Fluid balance c. Muscle contraction d. All of these are correct
d. all of these are correct
Vegetarians have a lower risk of: a. diabetes. b. cardiovascular disease. c. high blood pressure. d. all of these are correct
d. all of these are correct
protein denaturation can be caused by: a. an increase in temperature b. a change in pH c. the presence of alcohol d. all of these are correct
d. all of these are correct
Which of the following is TRUE of protein needs in athletes? a. Strength and endurance athletes may require 50-100% more protein than the RDA. b. Protein supplements are not typically necessary as long as kcal needs are met. c. It is unlikely that protein requirements in excess of the AMDR would be required. d. All of these statements are correct.
d. all of these statements are correct.
deamination: a. is the removal of the amino group from an amino acid b. must occur prior to using an amino acid for energy c. occurs before an amin acid is able to enter the citric acid cycle d. all of these statements are true
d. all of these statements are true
what is true about the protein in the modern american diet? a. protein deficiency is common in the United States. b. people who choose a vegetarian diet are deficient in protein. c. extra protein in the diet promotes weight loss d. approximately 2/3 of the dietary protein comes from meat
d. approximately 2/3 of the dietary protein comes from meat
Individuals with the genetic disorder phenylketonuria (PKU) should limit their intake of foods containing: a. carbohydrate. b. iron. c. monosodium glutamate. d. aspartame.
d. aspartame
all but one statement explains why protein-energy malnutrition develop more rapidly in children than adults. Which one is NOT? a. protein needs per unit of body weight are higher for children b. adequate energy is essential for growth c. proteins are important in immune function to fight infection d. breast milk contain inadequate protein and energy
d. breast milk contains inadequate protein and energy
gene expression: a. always results in protein formation b. is not affected by the level of nutrients in the body c.occurs for all genes through the body at all times d. is the process whereby the information coded in a gene is used to produce a product
d. is the process whereby the information coded in a gene is used to produce a product
Which of the following statements is true about protein digestion? a. denaturation of protein takes place in the small intestine. b. hydrochloric acid is used to convert peptides into amino acids. c. much dietary protein is lost in the feces. d. most protein digestion takes place in the small intestine.
d. most protein digestion takes place in the small intestines
proteins are unique in terms of their chemical structure when compared to carbohydrate and lipids because they contain: a. carbon b. hydrogen c. oxygen d. nitrogen
d. nitrogen
A(n) ____________ bond links one amino acid to the next. a. disulfide b. ionic c. glycosidic d. peptide
d. peptide
which condition represents a state of negative nitrogen balance? a. pregnancy b. meeting body needs for protein c. wound healing d. turning excess body protein to fat.
d. turning excess body protein to fat
Deamination is the removal of the amino group NH2 and converted to the less toxic ______ molecule. This occurs in the liver. a. nitrogen b. hydroxyl c. ammonia d. urea
d. urea
all of the following situation require amino acid deamination EXCEPT: a. wound healing b. illness c. injury d. surgery
a. wound healing
which condition represents a state of positive nitrogen balance? a. would healing b. illness c. injury d. surgery
a. wound healing
what is the name of the nitrogen group released by deamination? a. metabolizing amino acids to produce energy b. manufacturing enzymes c. producing glucose form amino acids d. converting amino acids to fat
b. manufacturing enzymes
A chemical score is calculated by comparing the amount of the limiting amino acid in the test protein with the amount of that amino acid in a reference protein such as: a. egg protein. b. human muscle protein. c. wheat protein. d. soy protein.
a. egg protein
Amino acids that cannot be made by the adult human body are termed: a. essential. b. hydrolyzable. c. incomplete. d. complete.
a. essentail
which of the following does NOT supply amino acids to the amino acid pool? a. fruits b. grains c. body muscle d. collagen
a. fruits
If a "limiting amino acid" is missing in the diet: a. it can be replaced with another during protein synthesis b. it can be synthesized in the body if its non-essential c. gene expression will alter to compensate for it. d. it is usually due to the deamination and burning of that amino acid.
b. it can be synthesized in the body if its non-essential
Which of the following is most likely to result from a chronic deficiency of protein and energy? a. PKU b. Marasmus c. Gallstones d. Increased resistance to infection
b. marasmus
Amino acids can be used to synthesize proteins that the body needs to become _________ hormones, and blood. a. energy, energy reserves b. muscle, enzymes c. adipose, cellulose d. all answer choices are correct
b. muscles, enzymes
Linkage of amino acids in a protein molecule is accomplished by: a. denaturation b. peptide bonds c. transamination d. connection of acid groups
b. peptide bonds
what is role of genes in synthesizing protein? a. genes prevent protein degradation b. genes maintain a constant supply of amino acids c. genes must be obtained from the food supply d. genes provide the code to synthesize proteins.
d. genes provide the code to synthesize protein
The pH lowering effects of ______convert pepsinogen to pepsin a. hydrochloric acid b. sulfuric acid c. acetic acid d. citric acid
a. hydrochloric acid
Which of the following terms can be used to describe a protein? a. Polypeptide b. Branched amino acid chain c. Polysaccharide d. Monopeptide
a. polypeptide
during digestion, if there is an excess of any one amino acid, more of it will be absorbed. a. true b. false
a. true
enzymatic protein digestion begins in the stomach. a. true b. false
a. true
phenylketonuria is an inherited disease in which the body cannot metabolic the amino acid phenylalanine. a. true b. false
a. true
How are protein needs determined? a. measure the changes in body weight over time. b. compare nitrogen consumed with the amount excreted by the body. c. utilize the levels established by the Dietary Reference Intakes (DRIs) d. estimate the Acceptable Macronutrient Distribution Range (AMDR) for age, gender, and activity.
b. compare nitrogen consumed with the amount excreted by the body
Kwashiorkor is a form of protein-energy malnutrition in which a deficiency of energy in the diet causes severed body wasting. a. true b. false
b. false
Negative nitrogen balance occurs when there is an increase in total body proteins a. true b. false
b. false
Protein digestion begins in the mouth a. true b. false
b. false
Protein malnutrition occurs more frequently in adults than young children as a result of decreased physical activity a. true b. false
b. false
in order to meet protein requirements, people should take supplements even if their diet is not deficient in protein a. true b. false
b. false
the shape of a protein is NOT important for its function? a. true b. false
b. false
transcription is the process of translation gah emRNA code into the amino acid sequence a polypeptide chain. a. true b. false
b. false
If the shape of a protein is altered due to a genetic mutation, the _______________ of the protein may be affected. a. nutritional value b. functionality c. taste d. texture
b. functionality
A limiting amino acid: a. does not supply the element nitrogen. b. is present in short supply relative to the body's need. c. cannot be used by the body during protein synthesis. d. is used to synthesize non-protein molecules that contain nitrogen.
b. is presentt in short supply relative to the body's need
The amino acid pool refers to amino acids: a. which are soluble in bodily fluids. b. present in body tissues and fluids and that are available for protein synthesis or to generate ATP. c. which are used by the body for building muscle tissue. d. which the body is not able to make and must be supplied by the diet.
b. present in body tissues and fluids and that are available for protein synthesis or to generate ATP.
The three-dimensional shape of a protein is determined by the: a. ratio of nonessential to essential amino acids present in the polypeptide chain. b. sequence of amino acids in the polypeptide chain. c. carbon to nitrogen ratio in the polypeptide chain. d. the number of peptide bonds present in the polypeptide chain.
b. sequence of amino acids in the polypeptide chain
Where does chemical digestion of protein begin? a. mouth b. stomach c. small intestine d. large intestine
b. stomach
Where does the digestion of protein BEGIN? a. mouth b. Stomach c. small intestine
b. stomach
Complete protein sources can be found in which MyPyramid food group? a. Fats and oils b. Fruits and vegetables c. Dairy d. Grains
c. dairy
disruption of a protein's normal configuration due to heat or acidity is known as: a. hydrogenation b. acculturation c. denaturation d. condensation
c. denaturation
The primary source of protein for most of the world's population is: a. meat. b. dairy. c. grains and vegetables. d. fruits.
c. grains and vegetables
Positive nitrogen balance can occur: a. when an individual is wasting as a result of protein-energy malnutrition. b. if protein intake does not meet an individual's protein requirements. c. in a rapidly growing child. d. when total body nitrogen balance does not change for 30 days.
c. in a rapidly growing child
Food allergies can result when a protein in the diet: a. is not absorbed and is eliminated in the feces. b. is filtered out of the blood and into the urine. c. is absorbed without being completely digested. d. provides amino acids that are not normally found in the human body.
c. is absorbed without being completely digested
sickle cell anemia: a. is caused by a protein deficiency b. is not a serious disease c. is caused by a change int he amino acid sequence of hemoglobin d. only affects the elderly
c. is caused by a change in the amino acid sequence of hemoglobin
Excess amino acids can be converted into fatty acids and stored as _______ in _____tissue. This can contribute to weight gain. a. cholesterol- adipose b. amino acids- muscle c. triglycerides- adipose d. cholesterol- muscle
c. triglycerides, adipose