Deck 6: Proteins and Amino Acids

Question 1

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.

Answer 1

C

Question 2

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.

Answer 2

B

Question 3

In the US,most dietary protein comes from:

A)animal sources.
B)beans.
C)nuts.
D)vegetables.

Answer 3

A

Question 4

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.

Question 5

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.

Question 6

A(n)____________ bond links one amino acid to the next.

A)disulfide
B)ionic
C)glycosidic
D)peptide

Question 7

Which of the following terms can be used to describe a protein?

A)Polypeptide
B)Branched amino acid chain
C)Polysaccharide
D)Monopeptide

Question 8

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

Question 9

All of the following components are always associated with an amino acid EXCEPT:

A)an amino group.
B)an acid group.
C)a phosphate group.
D)a side chain (functional group).

Question 10

Which statement about dietary protein sources is FALSE?

A)Animal products are the most highly concentrated sources of protein.
B)Plant sources of protein are typically rich in fiber and phytochemicals.
C)Legumes provide about as much protein per ½ cup serving as a cup of milk.
D)Most people in the U.S.need protein supplements to meet dietary requirements.

Question 11

Food allergies involve an interaction between a dietary protein and:

A)the immune system.
B)the excretory system.
C)DNA.
D)RNA.

Question 12

Which statement about amino acid absorption is FALSE?

A)Absorption of larger polypeptides occurs commonly in healthy adults.
B)Groups of similar amino acids share the same transport system.
C)If one amino acid is supplemented,it can slow the absorption of other amino acids.
D)Dipeptides and tripeptides are broken down to individual amino acids before leaving the mucosal cells of the small intestine.

Question 13

Which nutrient is found in plant protein foods but not in animal protein foods?

A)Iron
B)Zinc
C)Calcium
D)Fiber

Question 14

Of ____ amino acids commonly found in food proteins,____ are dispensible.

A)20; 9
B)11; 9
C)20; 11
D)24: 16

Question 15

Protein differs from 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.

Question 16

Protein denaturation can:

A)alter the three-dimensional shape of a protein.
B)decrease the nutritional value of a protein.
C)alter the sequence of amino acids in a protein.
D)break the peptide bonds holding a protein together.

Question 17

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

Question 18

The primary source of protein for most of the world's population is:

A)meat.
B)dairy.
C)grains and vegetables.
D)fruits.

Question 19

Amino acids that cannot be made by the adult human body are termed:

A)essential.
B)hydrolyzable.
C)incomplete.
D)complete.

Question 20

The enzymes trypsin and chymotrypsin:

A)break large polypeptides into smaller peptides.
B)are needed to denature proteins.
C)rearrange the sequence of amino acids in a polypeptide.
D)are needed to make nonessential amino acids.

Question 21

Which group has the highest protein requirement (per unit of body weight)?

A)Infants
B)Adults who exercise regularly
C)Adult women
D)Elderly men

Question 22

Which of the following is a TRUE statement?

A)Protein requirements decrease during injury and illness.
B)Most Americans do not consume enough protein.
C)The amount of protein used by the body is estimated by calculating nitrogen losses.
D)All of these statements are true.

Question 23

Protein requirements are in part based on a person's:

A)body weight.
B)age.
C)health status.
D)All of these are correct.

Question 24

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.

Question 25

Protein quality is determined by:

A)comparing the non-essential amino acid profile in a food with that in a reference protein.
B)the biological activity of the actin and myosin filaments in meat products.
C)how efficiently a protein in the diet can be used to make body proteins.
D)the ratio of nonessential to essential amino acids present in a food.

Question 26

An antibody:

A)is a type of protein that helps protect the body from foreign substances.
B)catalyzes chemical reactions in the body.
C)helps circulate lipids in the blood.
D)regulates the acid-base balance (pH)in the body.

Question 27

Hemoglobin is an example of:

A)a defense protein.
B)a transport protein.
C)an enzyme.
D)an immune protein (antibody).

Question 28

Protein-energy malnutrition is characterized by:

A)increased susceptibility to food allergies.
B)wasting and increased susceptibility to infection.
C)excessive urinary output.
D)hyperglycemia.

Question 29

The synthesis of glucose from certain amino acids involves:

A)deamination.
B)transcription.
C)translation.
D)transamination.

Question 30

Obtaining protein from plant foods may be advantageous because plant foods:

A)are typically good sources of fiber.
B)may contain healthy poly- and mono- unsaturated fats.
C)may lower blood cholesterol when consumed regularly.
D)All of these statements are correct.

Question 31

Proteins regulate which of the following body processes?

A)Acid-base balance
B)Fluid balance
C)Muscle contraction
D)All of these are correct

Question 32

The waste product resulting from the deamination of a protein is:

A)ketone bodies.
B)urea.
C)lactate.
D)CO₂.

Question 33

Excessive intake of animal protein foods could cause:

A)excessive bone mineralization,causing brittleness.
B)a diet to be too low in energy.
C)increased waste production overworking the liver.
D)an increased risk of heart disease.

Question 34

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.

Question 35

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.

Question 36

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.

Question 37

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.

Question 38

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,

Question 39

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.

Question 40

Gene expression and protein synthesis involve:

A)messenger RNA.
B)transcription
C)translation.
D)All of these choices.

Question 41

Heating a protein causes:

A)transamination.
B)deamination.
C)denaturation.
D)all of these.

Question 42

Isoflavones are chemically similar to the hormone:

A)testosterone.
B)cortisol.
C)estrogen.
D)insulin.

Question 43

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.

Question 44

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.

Question 45

Vegetarians have a lower risk of:

A)diabetes.
B)cardiovascular disease.
C)high blood pressure.
D)All of these are correct.

Question 46

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.

Question 47

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

Question 48

The basic building blocks of proteins are:

A)monosaccharides.
B)amino acids.
C)sterols.
D)ketone bodies.

Question 49

The AMDR for protein intake is _______% of energy intake.

A)20-35
B)45-65
C)30-45
D)10-35

Question 50

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.

Question 51

Regular soy consumption may help:

A)increase fertility.
B)lower blood LDL cholesterol levels.
C)improve athletic performance.
D)reduce muscle fatigue.

Question 52

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

Question 53

Protein complementation is most important for people who are:

A)vegan vegetarians.
B)recovering from surgery.
C)lacto-ovo vegetarians.
D)consumers of both plant and animal foods.

Question 54

Which of the following is the best dietary source of isoflavones?

A)Whole milk
B)Soy products
C)Citrus fruits
D)Beef

Question 55

Which of the following functions is performed by proteins in the body?

A)Transport
B)Structure
C)Immunity
D)All of these functions are performed by proteins.

Question 56

__________________ 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

Question 57

Which metabolic waste product increases when amino acids are converted to other metabolic intermediates?

A)Ammonia
B)Pyruvate
C)CO₂
D)Bilirubin

Question 58

Individuals with the genetic disorder phenylketonuria (PKU)should limit their intake of foods containing:

A)carbohydrate.
B)iron.
C)monosodium glutamate.
D)aspartame.

Question 59

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

Question 60

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.

Question 61

A measure of protein quality determined by comparing the amount of nitrogen retained in the body with the amount absorbed from the diet is called the:

A)chemical score.
B)biological value.
C)protein efficiency ratio.
D)net protein utilization.

Question 62

Complete protein sources can be found in which MyPyramid food group?

A)Fats and oils
B)Fruits and vegetables
C)Dairy
D)Grains

Question 63

A complete dietary protein:

A)contains the element sulfur.
B)has been hydrolyzed so that digestion is not necessary.
C)provides essential amino acids in the proportion needed to support protein synthesis.
D)has a low biological value.