Chapter 6

gene

A DNA segment that codes for a specific protein

sickle-cell anemia

A blood disorder caused by a genetic defect in the development of hemoglobin. Causes the red blood cells to distort into a sickle shape and can damage organs and tissues

digestibility

A foods capacity to be broken down so that it can be absorbed

protein-energy malnutrition (PEM)

A lack of sufficient dietary protein and/or caloroies

amino acid pools

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

B

A medical condition that is a genetic defect caused by a change in the amino acid sequence is __________. A) diverticulitis B) sickle cell anemia C) edema D) celiac disease

RNA

A molecule that carries out the orders of DNA

urea

A nitrogen-containing waste product that is excreted in urine

vegetarian

A person who doesn't eat meat, fish, or poultry or sometimes foods from these animal sources

B

A protein that acts as a hormone is ________. A) collagen B) insulin C) methionine D) pepsin

incomplete protein

A protein that is low in one or more of the essential amino acids. Protein from plant sources is an example

complete protein

A protein that provides all the essential amino acids that your body needs, along with some nonessential amino acids. Soy protein and protein from animal sources are examples

collagen

A ropelike, fibrous protein that is the most abundant protein in your body

protein digestibility corrected amino acid score (PDCAAS)

A score measured as a percentage that takes into account both digestibility and amino acid profile and gives a good indication of the quality of a protein

marsamus

A state of PEM where there is a severe deficiency of calories that perpetuates wasting; also called starvation

kwashiorkor

A state of PEM where there is a severe deficiency of dietary protein

precursor

A substance that is converted to another substance in the body

transfer RNA (tRNA)

A type of RNA that collects the amino acids within the cell that are needed to make a specific protein

messenger RNA (mRNA)

A type of RNA that copies the genetic information encoded in DNA and carries it out of the nucleus of the cell to synthesize the protein

A

A vegetarian diet may be low in ________. A) omega-3 fatty acids and vitamin B12 and D B) Vitamins B1, B2 and C C) vitamins D and K and fiber D) omega-3 fatty acids and vitamins E and K

B

All amino acids contain carbon, hydrogen, oxygen and ________. A) magnesium B) nitrogen C) sulfur D) iron

D

Amino acids that the body can never synthesize are called _______. A) conditionally essential amino acids B) required amino acids C) nonessential amino acids D) essential amino acids

B

An example of complemented proteins is _______. A) ham and cheese omelet B) hummus prepared with chickpeas and sesame seeds C) lettuce and tomato sandwich with mayonnaise D) butternut squash bisque soup topped with croutons

proteins

Compounds in your body that consist of numerous amino acids and are found in all living cells

D

Consistently eating too many high-protein foods can lead to a higher risk for ________. A) marasmus B) type 1 diabetes C) kwashiokor D) heart disease, kidney problems, and calcium loss from bones

D

Growing children and adolescents are in _______. A) negative nitrogen balance B) equilibrium C) nitrogen balance D) positive nitrogen balance

complemented proteins

Incomplete proteins that are combined with modest amounts of animal or soy proteins or with other plant proteins that are rich in the limiting amino acids to create a complete protein

B

Legumes are in which two USDA MyPlate groups? A) Grains and Vegetables B) Proteins and Vegetables C) Fruits and Vegetables D) Proteins and Fruits

conditionally essential amino acids

Nonessential amino acids that become essential if the body cannot make them, such as during bouts of illness

C

Protein bars, compared to a peanut butter sandwich, are most likely to be _______. A) lower in calories, fat, and sugar B) higher in fiber, fat, and sugar C) more expensive plus higher in saturated fat and sugar D) cheaper and lower in saturated fat and sugar

D

Protein synthesis is directed by the _______ in the nucleus of the cell A) transfer RNA B) messenger RNA C) ribosome D) DNA

hormones

Protein- or lipid-based chemical messengers that initiate or direct a specific physiological response. Insulin, glucagon, and estrogen are examples

C

Proteins are digested by enzymes in the __________. A) stomach and large intestine B) mouth and small intestine C) stomach and small intestine D) mouth and stomach

antibodies

Proteins made by your body to bind to and neutralize foreign invaders, such as harmful bacteria, fungi and viruses, as a part of the bodys immune response

transport proteins

Proteins that carry lipids (fat and cholesterol), oxygen, waste products, and vitamins through the blood to various organs and tissues, or that serve as channels to allow substances to pass through cell membranes

enzymes

Substances that act as catalysts and speed up reactions

catalysts

Substances that aid and speed up reactions without being changed, damaged, or used up in the process

buffers

Substances that help maintain the proper pH in a solution by attracting or donating hydrogen ions

B

Substances that speed up reactions without being changed or used up are _______. A) buffers B) catalysts C) hormones D) transporters

coenzyme

Substances, often vitamins, that are needed by enzymes to perform many chemical reactions in your body

False

T/F Americans are eating more red meat than they were in the 1970s

False

T/F Approximately one-half of your daily calories should come from protein

True

T/F Eating too much protein-rich food may increase your blood risk of heart disease

False

T/F Most Americans are falling short of their protein needs

False

T/F Protein bars are needed if you are very active

True

T/F Proteins increase satiety after a meal

False

T/F Soy is not as good as a source of dietary protein as fish

False

T/F Vegetarian athletes are at a competitive disadvantage compared with non-vegetarian competitors

False

T/F You can digest the protein in pasta as easily as the protein in a chicken breast

True

T/F Your body can use protein as an energy source

nonessential amino acids

The 11 amino acids that the body can synthesize

acid group

The COOH group that is part of every amino acid, also called the carboxyl group

edema

The accumulation of excess fluid in the spaces surrounding your cells, which causes swelling of the body tissue

denaturation

The alteration of a proteins shape, which changes the structure and function of the protein

limiting amino acid

The amino acid that is in the shortest supply in an incomplete protein

DNA

The blueprint in cells that stores all genetic information. DNA remains in the nucleus of the cell and directs the synthesis of proteins

peptide bonds

The bonds that connect amino acids, created when the acid group of one amino acid is joined with the nitrogen-containing amine group of another amino acid

amino acids

The building blocks of protein. They contain carbon, hydrogen, and nitrogen. Composed of an acid group, an amine group, and a unique side chain

B

The chemical bonds that connect amino acids are called ___________. A) ionic bonds B) peptide bonds C) glycosidic bonds D) amino bonds

protein turnover

The continual process of degrading and synthesizing protein. When the daily amount of degraded protein is equivalent to the amount that is synthesized, you are in protein balance

fluid balance

The equal distribution of water throughout your body and within and between cells

protein quality

The measure of a proteins digestibility and how its amino acid pattern compares with your bodys needs. Proteins that are more easily digested have a complete set of amino acids are of higher quality

connective tissue

The most abundant tissue type in the body. Made up primarily of collagen, it supports and connects body parts as well as providing protection and insulation

essential amino acids

The nine amino acids that the body cannot synthesize; they must be obtained through dietary sources

amine group

The nitrogen-containing part (NH2) of an amino acid

D

The organ that determines what happens to the amino acids after they enter the bloodstream is the ________. A) kidneys B) small intestine C) pancreas D) liver

D

The primary organ responsible for excreting nitrogen-containing waste is the ________. A) lungs B) skin C) feces D) kidneys

B

The quality of a protein is determined by the ________. A) proteins ability to be denatured B) digestibility of the protein and the types and amounts of amino acids C) size of the protein D) body's need for the protein

60

The recommended daily protein intake for a healthy adult weighing 165 pounds is ______ grams.

side chain

The side group of an amino acid that provides it with its unique qualities; also referred to as the R group

nitrogen balance

The state in which an individual is consuming the same amount of nitrogen (from protein) in the diet as he or she is excreting in the urine

immunity

The state of having built up antibodies to a particular foreign substance so that when particles of the substance enter the body, they are destroyed by the antibodies

amino acid profile

The types and amounts of amino acids in a protein

B

What is a benefit of consuming soy foods? A) Soy foods provide an excellent source of vitamin B12 B) Soy foods provide high-quality protein C) Soy foods provide a healthy source of cholesterol D) Soy foods increase HDL cholesterol level

B

When the amine group is removed, the carbon-containing component of amino acids can be ______. A) used to make DNA B) used for energy C) transformed into muscle mass D) converted to protein