Chapter 6

Question 1

Are the building blocks of proteins and are organic compounds that is composed of hydrogen, carbon, an amino group (NH3) and an acid group (COOH).

Answer 1

Amino Acid

Question 2

Amino acids that the body can not make and must be obtained through diet. Ex. Histidine and Leucine.

Answer 2

Essential amino acid

Question 3

Also known as dispensable amino acid are amino acids that the body can make. Ex. Alanine and Glutamic.

Answer 3

Non essential amino acid

Question 4

An amino acid that is normally essential but must be obtained through diet when the need for it exceeds the body’s ability to make it.

Answer 4

Conditionally essential amino acid

Question 5

A bond that connects the acid end of one amino acid to the amino end of the other one to form a protein chain.

Answer 5

Peptide bond

Question 6

When proteins are subjected to heat, acid, or other conditions that disturb or destroy their stability. Proteins uncoils and lose their shape and eventually lose their ability to function. Proteins are denatured during digestion when they are exposed to hydrochloric acid (stomach acid).

Answer 6

Denaturation

Question 7

Is an enzyme that breaks down proteins and hydrolyzes polypeptides.

Answer 7

Protease

Question 8

A protein that is used for a chemical reaction. Ex. Peptidase

Answer 8

Enzyme

Question 9

When broken down, amino acids mix with amino acids from diet in the cells and circulating blood.

Answer 9

Amino acid pool (including “location”)

Question 10

The process where amino groups are removed from amino acids and transferred to keto-acids.

Answer 10

Transamination

Question 11

The process of producing ammonia (NH3) a toxic compound during protein/amino metabolism.

Answer 11

Deamination

Question 12

Is when an essential amino acid supplied is less than the amount needed for protein synthesis.

Answer 12

Limiting amino acid

Question 13

How many grams does an ounce of most protein foods deliver?

Answer 13

7 grams of protein

Question 14

A person who regularly consumes a high-protein diet

Answer 14

Should drink plenty of water to dilute and excrete urea from the body.

Question 15

Is elevated in individuals with heart disease.

Answer 15

Homocysteine

Question 16

Converts inactive pepsinogen to its active form, pepsin and uncoils or denatured each protein’s tangled strand so that digestive enzymes can attack the individual peptide bonds.

Answer 16

Hydrochloric acid

Question 17

What special element does protein contain that carbohydrate and fat do not?

Answer 17

Nitrogen

Question 18

Describe the structure of proteins, including the levels, how shape affects function in proteins, and what happens when proteins are denatured. What do the R groups or side chains do in the amino acid molecule?

Answer 18

There are levels of protein structures: primary, secondary, tertiary, and quaternary protein structures. Primary protein structure is the sequence of a chain of amino acids. Secondary protein structure is the local folding of the polypeptide chain into helices or sheets. Tertiary protein structure is the three-dimensional folding pattern of a protein due to side-chain interaction, and quaternary protein structure is more than one amino acid chain. The shape affects the function of proteins because the shape predicts how a protein interacts or binds with other molecules. When proteins are denatured, proteins uncoil and lose their shape and function. R groups or side chains bond with one another to hold the length of a protein in a certain conformation.

Question 19

How may amino acids be metabolized in the body?

Answer 19

Amino acids are deaminated, which is it being stripped of their nitrogen-containing amino group and broken down to create energy for use, glucose, nonessential amino acids, cholesterol, fat, or ketone bodies.

Question 20

Briefly describe how proteins are synthesized.

Answer 20

Proteins are synthesized through transcription and translation. In transcription, a template of DNA is used to make mRNA which carries the code and attaches it to a ribosome. In translation, mRNA specifies the sequence and translates the code into which amino acid lines up for protein synthesis.

Question 21

What are the roles of proteins in the body?

Answer 21

They are structural materials; for example, they are the building blocks of muscles, blood, and skin, and they replace dead or damaged cells. They act as enzymes and hormones; oxytocin and prolactin support lactation, and thyroxine regulates the body’s metabolic rate. They act as regulators of fluid balance, acid-base regulators, transporters, antibodies, a source of energy and glucose, and other roles like making other compounds.

Question 22

What determines protein quality? What are some high-quality, complete proteins?

Answer 22

What determines the protein quality is the protein’s digestibility and amino acid composition. Some high-quality or complete proteins are foods from animals like meat, seafood, poultry, eggs, milk, etc.

Question 23

What is a complementary protein? Do complementary proteins have to be eaten together at a meal?

Answer 23

Complementary proteins are two or more dietary proteins whose amino acids complement each other; when one amino acid is limited in one, it is supplied by the other and is sufficient to support health. Complementary proteins need to be consumed each day but not together in one meal.

Question 24

How much protein do adults need? Be able to calculate this if given a body weight in pounds.

Answer 24

The protein RDA for adults is 0.8 gram per kilogram, 50 to 175 grams per day, 200-700 kcalories, and the AMDR is 10-35 percent each day. To convert pounds into kilograms is dividing the pounds by 2.2 then multiply the answer by 0.8.

Question 25

Discuss the health consequences of too much or too little protein or too much of the wrong type.

Answer 25

Some health consequences of too much or a high protein diet are chronic diseases like heart disease, cancer, osteoporosis, obesity, and kidney stones. A too little or deficient protein diet can cause slowed growth, impaired brain, and kidney function, weakened immunity, and inadequate nutrient absorption.

Question 26

Essential Amino Acids

Answer 26

Histidine
Isoleucine
Leucine
Lysine
Methionine
Phenylalanine
Threonine
Tryptophan
Valine

Question 27

Nonessential Amino Acids

Answer 27

Alanine
Arginine
Asparagine
Aspartic acid
Cysteine
Glutamic acid
Glutamine
Glycine
Proline