NSC101: Chapter 6

What are conditionally essential amino acids?

Those amino acids that are normally nonessential but must be supplied through the diet when the need for it exceeds the body's ability to produce it

Which of the following statements is true of a vegan diet?

Vegan children may not consume enough plant sources of protein to build bone and muscle tissue

Which of the following helps protect the stomach lining from the action of strong hydrochloric acid produced in the stomach?

a coat of mucus

_______ ___________ are the building blocks of protein.

amino acids

In making recommendations for protein intake, the DRI committee took into consideration that the protein in a normal diet would be:

combination of animal and plant sources

Eating a variety of protein foods from plants so that amino acids that are low in some foods will be supplied by the others are:

complementary proteins

Protein digestibility is highest for which foods?

eggs

The most easily digestible form of protein can be found in which of the following foods?

eggs

an _________ v

enzyme

Which amino acids cannot be made by the body or made in quantities great enough to meet the body's needs?

essential

Which amino acids cannot be synthesized in amounts sufficient to meet physiological needs?

essential amino acids

t/f: In high doses, tryptophan can improve nausea and skin disorders.

f

T/f: Commercial shakes and energy bars have proven to be the best protein sources to support weight-loss efforts.

false

Which of the following foods is not included in a lacto-ovo vegetarian diet?

fish

Which of the following food sources can vegans use to obtain the required quantity of omega-3-fatty acids in their diets?

flax seed

Proteins can be denatured by all of the following EXCEPT

freezing

__________ is a protein that forms in grain foods, is best known for providing a pleasing stretchy texture to yeast breads.

gluten

All of these are proteins EXCEPT ________.

glycogen

an athlete consumes large amounts of meat in an effort to build extra muscle tissue. Identify the correct statement about the effect of excess consumption of meat.

he body utilizes excess amino acids as fuel or stores them as fat.

Cells will do all of the following to create their own working proteins from available amino acids except

hold partially completed proteins until the diet provides the missing amino acids

What are chemical messengers that travel through the bloodstream, resulting in a cellular response? Many are made from amino acids.

hormones

Problems with consuming too much protein include all the following EXCEPT:

increase in electrolytes from fluid retention seen with high protein intakes.

Which of the following is NOT a consequence of protein deficiency?

increased nutrient absorption from the digestive tract

What is NOT one of the beneficial characteristics of a vegetarian diet?

it provides more saturated fat

What are plants that accumulate nitrogen and are efficient at trapping nitrogen that farmers often grow them in rotation with other crops? These plants are often included with meat in the protein food groups.

legumes

What is the DRI for protein?

0.8 g/kg of body weight

Polypeptides are proteins that contain how many different kinds of amino acids?

10-50

There are ___ essential amino acids

9

T/F: Essential amino acids are those that play an important role in the body and can only be obtained through supplementation.

False; Essential amino acids are those that the body cannot make and must be provided by the diet.

_____ is/are important for the control of protein synthesis.

RNA

An adolescent girl has decided to adhere to a vegan diet. Her lunch consists of a tossed green salad that contains celery, tomatoes, cucumbers, and onions; whole-wheat crackers; and apple juice. What comment would you make about her complementary protein choices?

She should add garbanzo beans to her salad to obtain the protein combination she requires.

Which snack should someone who wants to stimulate muscle protein synthesis consume after a strength-building exercise?

Skim milk

The roles of protein in the body include which of the following?

balance of acids and bases providing energy transport of substances in the bloodstream cell structure

Protein functions as the body's _______ helping maintain normal PH

buffers

Digestion of food proteins in the stomach is carried out by the enzyme pepsin, which is activated in the presence of __________. This enzyme reaction attacks food protein's __________.

d. gastric acid; peptide bonds

Heat, radiation, alcohol, acids, bases, and the salts of heavy metals causes a protein to unfold and inactivate itself, which is called ____________

denaturation

Proteins attract water and hold it within blood vessels, preventing it from freely flowing into the spaces between the cells. This is an example of how protein is used for:

maintaining fluid and electrolyte balance

What protects the stomach from digesting itself?

mucus lining of the stomach

Under normal circumstances, healthy adults are in

nitrogen equilibrium

All the following are functions of protein EXCEPT

primary energy source

Amino acids are needed each day to support the new growth and maintenance of cells because there is a continuous breakdown and synthesis of proteins within the body called

protein turnover

Proteins play several important roles in the body. What is NOT one of these?

providing an unlimited supply of energy

The _________ of the protein's side group (hollow, spiral, positively charged) determines the protein's function (hemoglobin, collagen, buffer).

shape

The variable part of an amino acid is the

side chain

What contains enzymes that split peptide strands into tripeptides, dipeptides, and amino acids? It is also where amino acids are absorbed.

small intestine

Protein digestion and denaturing begins in the __________

stomach

When amino acids are consumed in excess of what is needed, all the following are possible fates of the excess amino acids EXCEPT:

stored in muscle tissue

Negative nitrogen balance is seen in

surgery patients

t/f: Gelatin supplements cannot strengthen fingernails or restore a youthful look to the skin.

t

When amino acids are degraded for energy, their amine groups are stripped off and incorporated by the liver into _____ and sent to the kidneys for excretion.

urea

Who would benefit most from eating a variety of protein foods so that amino acids that are low in some foods will be supplied by the others?

vegan

Approximately the same amount of protein is provided by each of the following foods, which are all cooked or ready to eat: ½ cup legumes; 1½ cups broccoli; 1 oz cheese; and 2 T peanut butter. Which of these would be the most nutrient-dense food choice for protein?

½ cup legumes (122 cal)