Nutrition Midterm

mod 7 = 1-97

What is the most frequently consumed source of saturated fat in Americans' diets?

cheese

To make your salad more appealing yet still healthy, try to use __________.

a variety of vegetables

An example of a healthy, protein-laden vegetarian lunch is __________.

a salad with beans and tofu, and a bowl of bean soup

Which of the following is not a good protein source?

cucumbers

You do not need to eat meat to get enough protein in your diet, provided that you __________.

get enough protein from a variety of plant sources

Which of the following foods would have the lowest amount of protein per serving?

fruits

Which of the following plant foods have the highest quality of protein?

tofu

Which of the following foods provides a moderate amount of protein per serving?

corn

Which of the following foods would provide the highest quality protein in the smallest portion size?

chicken breast

Which of the following is true about the quality of protein?

Proteins from foods of animal origin are generally high-quality proteins.

Which of the following is true regarding the relationship between amino acids and protein?

Protein is made of essential and nonessential amino acids.

Once amino acids have entered the amino acid pool, their primary metabolic fate is to become part of a protein produced within individual cells. But this is not the only possible metabolic fate for amino acids. What could be a metabolic fate for an amino acid after it becomes part of the amino acid pool?

It could be used to produce glucose, make body fat. and for energy production.

t/f Approximately 50 percent of every protein molecule is composed of nitrogen.

false

How do we determine whether we are in protein balance?

measuring the amount of nitrogen consumed with the amount of nitrogen excreted

For nitrogen balance:

People who are injured or starving excrete more nitrogen than they consume.

Children are generally in positive nitrogen balance.

Most healthy adults are in neutral nitrogen balance.

t/f Enzymes are proteins, which catalyze chemical reactions.

true

Which of the following statements regarding enzymes is true?

The shape of the enzyme's active site determines its activity.

Enzymes are specific to specific chemical reactions.

Some enzymes require a coenzyme to be active.

To use amino acids for energy, the nitrogen must first be removed from the amino acid. This process is called __________.

deamination

Nitrogen that has been removed during deamination __________.

converted to urea and excreted through the urine

A nonessential amino acid is made __________.

by transferring the amino group from one amino acid to a keto acid. A keto acid is an amino acid without the amine group.

t/f Deamination occurs mostly in the brain.

false (mainly in the liver)

The bond that is formed when two amino acids join together is called __________.

a peptide bond

A chain of two amino acids is referred to as a __________.

dipeptide

A molecule with four to nine amino acids joined together by peptide bonds is referred to as __________.

oligopeptide

What compound carries the blueprint from DNA to the ribosomes during protein synthesis?

mRNA

DNA contains all the genetic information necessary for production of every protein the body makes.

An mRNA molecule is a copy of a gene on the DNA molecule.

Nuclear DNA cannot leave the nucleus.

When variations (also called mutations) occur within genes, the proteins that are encoded by those genes are modified. Many times, mutations occurring in genes do not result in noticeable effects on the proteins synthesized from them and are considered harmless. Other times, a genetic mutation may affect the final structure and function of a protein enough to result in disease. Which of the following statements correctly applies to the genetic disorders sickle-cell anemia or phenylketonuria?

The mutation that causes sickle-cell anemia results in production of hemoglobin proteins which crystallize causing misshapen red blood cells; some of them look like half-moons.

Amino acids are bound together by a chemical bond known as an _____ to form proteins.

peptide bond

t/f The side chain of an amino acid differentiates one amino acid from another

true

essential amino acids:

histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Amino acids found in the amino acid pool __________.

can be used for protein synthesis

pepsin

the active form of a digestive enzyme in the stomach that breaks polypeptide chains into smaller polypeptides.

Cleavage of proteins by pepsin in the stomach results in formation of ______ which get broken down further in the small intestine.

polypeptide strands

An amino acid chain made up of three amino acids joined together is called a

tripeptide

dipeptide

describes an amino acid chain made up of two amino acids joined together.

The 20 different _____ are the building blocks used for protein synthesis.

amino acids

amino acids pools

are stockpiles found in the blood and other cells of the body that can be used to build new proteins.

protein turnover

The continual process of degrading and synthesizing protein

denaturation

occurs when a protein is exposed to heat, acid, bases, or mechanical agitation resulting in unfolding of the protein, though the peptide bonds remain intact

amine group

The part of an amino acid that contains nitrogen

acid group

also known as the carboxyl group.

Single amino acids that are absorbed in the small intestine travel to the liver via the

portal vein

How does your body use the protein once it has been ingested?

The liver uses amino acids to create glucose.

Amino acids are used to create new proteins.

If calorie intake is inadequate, amino acids can be used for production of energy.

how many nonessential amino acids are there?

11

where does the digestion of polypeptides begins with the enzyme pepsin.

stomach

Which of the following statements regarding protein absorption is true?

Protein is absorbed as single amino acids or small peptide chains by the process of active transport

What is denaturation?

the uncoiling of the protein molecule by hydrochloric acid in the stomach

What secretions are needed to digest complex proteins into single amino acids for absorption?

proteases secreted from the pancreas and the small intestine

saliva from the salivary glands in the mouth

hydrochloric acid and pepsin in the stomach

There are _____ unique amino acids in the human body.

20

Which of the following actions or activities will not cause a protein's structure to break down?

gently stirring

Protein consumed in excess of body needs __________.

is stored as body fat

To estimate whether a person's protein intake is adequate to meet his or her protein needs, researchers __________.

use a nitrogen-balance procedure

The latest AMDR for Protein should make up between __________ of the day's total energy intake.

10-35%

Which of the following foods is a source of complete protein?

chicken breast

Limited amounts of surplus amino acids are stored in the body in _____.

amino acid pools

An 8-ounce glass of low-fat chocolate milk contains 160 kilocalories (kcal) and 8 grams of protein. What percent of the kcal in the milk comes from protein?

20%

Proteins play important roles in the body, including _____.

aiding in digestion, transporting nutrients through the blood, and fighting off the flu and other infections

Proteins act as ____________ and help to maintain proper pH in blood by picking up or donating hydrogen ions.

buffers

Which of these elements is found in proteins but not in carbohydrates and lipids?

nitrogen

What food can be eaten with brown rice to ensure all of the body’s amino acid needs are met?

black beans, tofu, or almonds

The process that destroys the shape and activity of proteins when heat, acid, salts, or pressure is applied is known as:

denaturation

A body that retains more nitrogen than it excretes is in _______.

positive nitrogen balance

(This means the body is storing more nitrogen than it is expelling, which supports tissue growth, repair, & protein synthesis.)

Unless carefully planned, vegan diets may be low in which of the following essential micronutrients?

vitamins: D, B12, calcium, and iron

Which of the following is a major function of protein in the human body?

Growth + maintenance of new tissues, synthesis of certain hormones, and maintaining fluid balance

Kwashiorkor is a type of protein-energy malnutrition that develops when

there is a severe deficiency of protein in the diet but an adequate intake of energy

After a person consumes a glass of soy milk, where does the majority of the digestion and absorption of the protein occur?

small intestine

The part of the protein molecule that contains nitrogen is called the ________.

amine group

Which of the following sources of protein has the highest digestibility?

pork

Which of the following is a source of complete protein?

soy milk

Complete protein is found abundantly in _____

meat

Protein synthesis is directed by a compound in the cell nucleus called _______

deoxyribonucleic acid (DNA)

A healthy immune system depends on an adequate supply of proteins that bind to and neutralize harmful invaders. What are these proteins known as?

antibodies

Charlie is a 22-year-old male nonathlete who weighs 70 kilograms. How much protein should he consume daily?

56

(70 × 0.8)

Which of the following will not denature a protein?

refrigerating milk

What happens to the amino acids that are absorbed after the digestive process is complete?

Many amino acids are used to build and maintain body tissues, make new clotting proteins, enzymes, antibodies, neurotransmitters, and other products

Some amino acids are degraded and the nitrogen excreted in urine while the carbon, hydrogen, and oxygen remains are used for energy, or are stored as fat.

A limited supply of all amino acids remains in amino acid pools in the blood and inside the cells.

An acceptable main dish for a lacto-ovo-vegetarian would be _____.

baked ziti w ricotta cheese, spinach, and tomato sauce

stir-fried tofu + vegetables over brown rice

cheese + broccoli omelet

Akiko is a 20-year-old female. How much protein does she need daily?

0.80 gram per kilogram body weight

A limited supply of amino acids stored in your blood and cells and used to build new proteins is called the________.

Amino acid pool

Jordan is a competitive athlete who takes protein powder. Excess proteins that aren't used for protein synthesis are_________.

converted to and stored as fat.

Which of the following is a potential fate of the carbon-containing remains of amino acids after they are broken down?

All of the above - They can be used as a glucose source, to make energy, and it can be stored as fat.

Deficiencies in protein, iron, zinc, calcium, vitamin D, riboflavin, vitamin B12, vitamin A, and omega-3 fatty acids are most likely among_______.

vegans

Maria recently adopted a vegan lifestyle. Which nutrients does she need to focus on to ensure that she does NOT develop deficiency symptoms?

Protein, iron, and zinc

Healthy pregnant and lactating women and adequately growing children are in ________ nitrogen balance.

positive

Compared to meat-derived proteins, plant proteins are typically_______.

incomplete

A diet that is too high in protein can increase the risk for all of the following EXCEPT

immune problems

t/f: Proteins are made of amino acids, which contain an acid group, an amine group, and a universal side chain.

false

t/f: Some amino acids from the amino acid pool are used to make hormones.

true

t/f: Excess amino acids are either broken down, stored in another form, or used as energy, with the nitrogen being converted to urea which is excreted in the urine.

true

t/f: Collagen protein is responsible for the elasticity in your skin and helps form scar tissue to repair injuries such as wounds.  Therefore, it is essential for humans to consume collagen protein in our diets to ensure health skin and efficient wound repair

false

The process of continually degrading and synthesizing protein is called ___________.

protein turnover

The limited supply of the amino acids exists in your blood and inside your cells and used to create proteins for the cells in the body is generally referred to as _________.

Amino acid pool

What is a good way to raise high-density lipoprotein (HDL) cholesterol levels?

Exercise more and lose excess weight

The primary lipid in the body is _____.

Triglycerides

The “backbone” of a triglyceride is a ____ molecule

Glycerol

What lipoproteins has the highest percentage of cholesterol?

Low-density lipoprotein (LDL)

Which of the following is a function of fat in the body

Insulate the body and regulate body temperature, enable the absorption of fat-soluble vitamins, cushion bones, organs and nerves.

The majority of trans fats in foods are created by food manufacturers through the process of

Hydrogenation

The Acceptable Macronutrient Distribution Range for total fat intake is

between 20 percent and 35 percent of a person’s daily energy intake

Which of these is healthiest?

a high level of high-density lipoprotein (HDL) cholesterol

Consumption of which of these dietary components raises low-density lipoprotein (LDL) cholesterol the most?

Saturated fats