Ch 7

A high-protein diet can affect the kidneys by

increasing the production of urea.

the protein transporter transferrin carries

iron (Ferritin is a storage protein for iron)

the protein transporter lipoprotein carries

large lipid molecules from the small intestine through the lymph and blood to body cells

Which proteins function as transporters for other nutrients?

lipoproteins transferrin

When carbohydrates are in short supply, the ______ can make glucose from amino acids present in body tissues.

liver

A(n) _______ amino acid, sometimes called dispensable, is one that can be synthesized by a healthy body in sufficient amounts.

nonessential

Plant proteins are a heart-healthy alternative to animal proteins because they typically contain less or no ______ than animal sources of protein.

saturated fat

food intolerance

Caused by an individual's inability to digest certain food components

_______ is a double-stranded molecule in a helical form.

DNA (Deoxyribonucleic acid)

This is 2 or more protein units joined together.

Quaternary

Which structural proteins make up more than a third of the body protein? (Check all that apply.)

collagen actin myosin The key structural proteins (collagen, actin, and myosin) make up more than a third of body protein and provide a matrix for muscle, connective tissue, and bone.

Healthy individuals who are not in periods of growth or recovering from an illness or injury need to consume protein in an amount that is ______ the amount lost in urine, feces, sweat, skin cells, hair, and nails.

equal to

A(n) _________ amino acid, also called indispensable, cannot be synthesized by humans in sufficient amounts, if at all, and must be included in the diet.

essential

Meat, poultry, fish, and eggs are a good source of all 9 _________ , or indispensable, amino acids.

essential

_____ -protein diets can lead to kidney problems and are not recommended for people with (or at risk for) kidney disease.

High

The RDA for protein would be higher

>in highly trained athletes. >during recovery from illness or injury.

If your carbohydrate intake is inadequate, the liver is forced to make glucose from ______.

>protein in body tissues >stored glycogen >amino acids in body tissues

The amino acids needed for the synthesis of protein are supplied by

>the diet. >recycling of body protein.

What can cause denaturation? (Check all that apply.)

Agitation Exposure to alkaline solutions Exposure to acid solutions Exposure to acid or alkaline solutions, enzymes, heat, or agitation can change a protein's structure, leaving it in a denatured state (Fig. 7-8). Alteration of a protein's 3-dimensional structure is called denaturation. Although denaturation does not affect the protein's primary structure, unraveling a protein's shape often destroys its normal biological function.

______ is known as "the disease the first child gets when the new child comes.

Kwashiorkor

_______ is known as "the disease the first child gets when the new child comes."

Kwashiorkor

Which of the following is the primary cause of marasmus?

Lack of food/nutrients

Most vital body proteins are in a constant state of breakdown, rebuilding, and repair. What is this process called?

Most vital body proteins are in a constant state of breakdown, rebuilding, and repair. This process, called protein turnover, allows cells to adapt to changing circumstances. For example, when we eat more protein than necessary for health, the liver makes more enzymes to process the waste product from the resulting amino acid metabolism—namely, ammonia—into urea. Overall, protein turnover is a process by which a cell can respond to its changing environment by increasing the production of needed proteins while reducing the production of proteins not currently needed.1

There are 4 groups that make up each amino acid. They are the hydrogen group, the acid group, the amino group, and the ______ group.

R group (AKA side chain)

What will happen if the DNA code contains errors?

Ribosomes will read the incorrect message. The polypeptide chain will be incorrect. Incorrect mRNA will be produced.

Which of the following describe the components of an amino acid?

Side chain Acid group Amino group

Which shape of the protein determines the function?

Tertiary

Protein deficiency is rarely an isolated condition and usually accompanies _____.

calorie deficiency lack of nutrients

If a food _______, it should allow for efficient incorporation of food-derived amino acids into body protein.

contains all 9 essential amino acids

Healthy individuals need to consume protein in an amount that replaces the protein lost in ____. (Check all that apply.)

hair feces urine

Amino acids are important in the synthesis of many ______, such as insulin and glucagon.

hormones

All of the following are components that make up an amino acid except

sodium

Where does the digestion of protein begin?

stomach

The amino group is in what form in the urine?

urea (The lost amino group (in the form of ammonia) is incorporated into urea in the liver, transported via the bloodstream to the kidneys, and excreted in the urine.)

The amino group from an amino acid is excreted in the

urine

the protein transporter retinol-binding protein carries

vitamin A

A ____ _____contains all of the essential amino acids but will have varying degrees of biological value.

complete protein

the protein transporter ceruloplasmin carries

copper

Nonessential amino acids are also called

dispensable amino acids.

Diets containing excessive amounts of protein ____ provide additional health benefits.

do not

Whenever Suzy eats spinach she gets an upset stomach. Suzy is most likely experiencing a

food intolerance

Chronic protein-energy malnutrition results in

marasmus

This is a measurement of how efficiently the absorbed food protein is converted into body tissue protein.

Biological value

Incorrect mRNA production and incorrect polypeptide chain production both result from an error in the _____ code

DNA or gene or genetic

_______ proteins are heart-healthy because they contain no cholesterol.

Plant

Which shape of the protein determines the linear sequence?

Primary

Amino acids that are dispensable

can be made from other amino acids

An amino acid without an amino group is called a

carbon skeleton

food allergy

causes immune response

Which of the following statements about kwashiorkor are true? Select all that apply.

>A young child may develop kwashiorkor when he is abruptly weaned from breast milk to starchy gruels. >Fatty liver is a possible >Edema is a possible consequence of kwashiorkor.

The most common nutritional concerns for infants and children following vegetarian and vegan diets are:

Iron Vitamin D Vitamin B12

Identify the different levels of protein organization. (Check all that apply.)

primary structure quaternary structure tertiary structure secondary structure The sequential order and strong peptide bonding of the amino acids in the polypeptide chain, called the primary structure, determine a protein's shape. Amino acids must be accurately positioned in order for the amino acids to interact and fold correctly into the intended shape for the protein. This, in turn, allows weaker chemical bonds to form between amino acids near each other and stabilizes the structure. This creates a spiral-like or pleated sheet shape called the secondary structure. The unique 3-dimensional folding of a protein, called tertiary structure, determines the protein's overall shape and physiological function. Thus, if a protein fails to form the appropriate configuration, it cannot function. In some cases, 2 or more separate polypeptides interact to form a large, new protein, with quaternary structure

Which hormone is made only from one amino acid?

thyroid hormones

Put the processes of protein digestion in the correct order, from start to finish.

1. Proteins are partially digested in the stomach by the enzyme pepsin and hydrochloric acid 2. The final digestion of protein to amino acids occurs in the small intestine. 3. Amino acids are absorbed into the portal vein and transported to the liver 4. Little dietary protein is present in the feces.

The Food and Nutrition Board recommends that protein intake does not exceed ___% of energy intake.

35%

Which of the following are the four (4) building blocks of DNA?

Guanine Cytosine Thymine Adenine

Blood proteins have what type of influence on body fluids?

Help to maintain body fluid

Which of the following is the amino acid that can be synthesized by a healthy body in sufficient amounts?

Nonessential (aka despinsable)

What is the reason why energy needs may not be met in infants and children following a vegetarian or vegan diet?

They consume a diet rich in high fiber, low calorie foods that cause fullness.

The blood proteins _______________ are important in maintaining fluid balance.

albumin globulin

Denaturation is the process of

altering the 3-dimensional structure of a protein.

A(n) ________ ________ is composed of 4 elements: a nitrogen, an acid, a hydrogen, and a side group.

amino acid

the protein transporter hemoglobin carries

oxygen (to the lungs and cells)

The bond that links amino acids together to form a protein is called a(an) ____ bond.

peptide

Amino acids are the basic elements used in the synthesis of ______.

protein

The nutrient that serves in the regulation and maintenance of the human body by aiding in fluid balance, cell synthesis and repair, and visual processes is

protein

Which macronutrient is a key component of the cells within the immune system and makes up many of the antibodies that defend the body from illness?

protein

A(n)_______ usually accompanies a deficiency of calories and nutrients.

protein deficiency

Proteins serve which of the following functions?

>Proteins regulate and maintain essential body functions. >Proteins aid in cell synthesis. >Proteins play a role in enzyme and hormone production.

How do proteins contribute to acid-base balance of the blood?

>Serve as buffers that resist changes in pH >Pump ions into and out of cells Proteins play an important role in regulating acid-base balance and body pH. For example, proteins located in cell membranes pump chemical ions into and out of cells

What individuals are at risk for PEM?

>Suffering from anorexia nervosa >Hospitalized patients >Living in poverty

An essential amino acid

>cannot be synthesized by humans in sufficient amounts. >must be included in the diet or a deficiency will occur.

Which population has a high prevalence of PEM?

Central America Protein deficiency rarely develops as an isolated condition. It most often occurs in combination with a deficiency of energy (and other nutrients) and results in a condition known as protein-energy malnutrition (PEM), or protein-calorie malnutrition (PCM).

Most of the ______ released throughout the body can be recycled to become part of the pool available for the synthesis of future proteins.

amino acids

What is the term used for the building blocks of proteins?

amino acids

A carbon skeleton is an amino acid without the _____ ______

amino group

Proteins from ______ are considered to be a good source of all 9 essential amino acids.

animals

Identify a key component of the immune system.

antibody proteins

The body links amino acids with peptide bonds in order to form

proteins

______ help regulate acid-base balance in the blood.

proteins

During the periods of mental stress, physical labor, and routine weekend sports, a person's protein needs _____.

remain unchanged

The process of protein turnover involves protein _____. (Check all that apply.)

repair breakdown rebuilding