Chapter 6: proteins

Question 1

What is the RDA for protein based on?

Answer 1

weight

Question 2

What is the RDA for protein?

Answer 2

0.8 g protein/ kg of body weight per day

Question 3

What percentage of total caloric intake should be from protein?

Answer 3

10-35%

Question 4

What groups of athletes are at risk for low protein intake?

Answer 4

distance runners, figure skaters, female gymnasts, and wrestlers who are dieting

Question 5

What groups of people require more protein?

Answer 5

children, adolescents, pregnant/lactating women, athletes, vegetarians

Question 6

protein functions

Answer 6

metabolism, cell growth, repair and maintenance, immunity, pH balance, fluid and electrolyte balance, and nutrient transport and storage, structural proteins, (energy)

Question 7

essential amino acids, how many are there?

Answer 7

cannot be produced by the body, must be obtained from food (9 of 20)

Question 8

nonessential amino acids

Answer 8

can be made by our bodies, but are also present in the diet

Question 9

amino acids are connected by

Answer 9

peptide bonds

Question 10

primary structure

Answer 10

sequential order of amino acids

Question 11

secondary structure

Answer 11

spiral shape due to chemical bonds between amino acids

Question 12

tertiary & quaternary structure

Answer 12

further folding into unique 3-dimensional shape

Question 13

how are proteins denatured?

Answer 13

when subjected to heat, acids/bases, heavy metals, alcohols

Question 14

what is denaturation?

Answer 14

proteins lose shape, it is irreversible and results in loss of protein function

Question 15

sickle cell anemia

Answer 15

change in one amino acid

Question 16

what contributes to the amino acid pool in the body?

Answer 16

amino acids from foods & amino acids from the breakdown of cells

Question 17

what is the amino acid pool used for in the body?

Answer 17

synthesis of non-protein compounds that contain nitrogen, body proteins, fat (stored as adipose tissue), glucose (used for energy), and energy produced from the amino acid carbon skeleton

Question 18

what happens to the excess nitrogen from amino acids if it doesn’t get used in the newly synthesized compound?

Answer 18

excess nitrogen in the form of ammonia used to synthesize urea in the liver, urea then excreted in the urine

Question 19

complete protein (high-quality) and examples

Answer 19

contains sufficient amounts of all 9 essential amino acids (animal proteins, soy, quinoa, chia)

Question 20

incomplete protein (low quality) and examples

Answer 20

does not contain all 9 essential amino acids in sufficient quantities (plant proteins)

Question 21

what happens if you only consume incomplete proteins that do not complement each other?

Answer 21

growth and health are compromised because some proteins cannot be synthesized

Question 22

complementary proteins

Answer 22

2 incomplete protein sources that supply all 9 essential amino acids together (beans and rice)

Question 23

do you have to eat complementary proteins at the same time to get a complete protein?

Answer 23

No

Question 24

what is edema caused by?

Answer 24

insufficient protein in the bloodstream, fluid does not get reabsorbed (fluid buildup)

Question 25

protein digestion in the mouth

Answer 25

only mechanical, proteins crushed by chewing and moistened by saliva

Question 26

protein digestion in the stomach

Answer 26

HCl denatures proteins and activates pepsin, pepsin breaks proteins into smaller chains or single amino acids

Question 27

protein digestion and absorption in the small intestine

Answer 27

pancreas produces proteases which are released into the small intestine -> proteases digest polypeptides into di and tri-peptides -> cells in the walls of the small intestine break down di and tri-peptides into single amino acids which are absorbed into the blood -> amino acids transported to the liver

Question 28

what are the two things that determine protein quality?

Answer 28

essential amino acid composition and digestibility

Question 29

what are the risks of too much dietary protein?

Answer 29

high cholesterol, heart disease, and kidney disease

Question 30

diets high in protein from animal sources are associated with what?

Answer 30

high blood cholesterol

Question 31

what are some alternative sources for protein?

Answer 31

dairy, legumes, eggs, nuts, and whole grains

Question 32

how much protein should you consume after resistance exercise for maximum protein synthesis?

Answer 32

~25 g

Question 33

what are amino acids used for if you consume over 25 g of protein after resistance training?

Answer 33

energy, muscle cannot utilize excess protein

Question 34

protein concentrate

Answer 34

extract protein from whole food 'typically 60-80% protein, 20-40% CHO and fat)

Question 35

protein isolate

Answer 35

additional filtering removes more CHO and fat (90-95% protein)

Question 36

protein hydrosylate

Answer 36

further processing breaks the bonds between amino acids (absorbed more quickly by body muscles)

Question 37

soy supplements

Answer 37

made from defatted soybean flakes (complete plant-based protein) & contains leucine (BCAA)

Question 38

how are soy supplements processed?

Answer 38

rinsed in alcohol and water to remove some of the phytoestrogen content

Question 39

is whey or soy supplement more effective?

Answer 39

whey

Question 40

pea supplements

Answer 40

protein is isolated from yellow split pea, has all essential amino acids except methionine, rich in BCAAs

Question 41

is absorption of pea supplement protein faster or slower than whey? casein?

Answer 41

slower than whey, faster than casein

Question 42

hemp supplements

Answer 42

not a complete protein (missing leucine and lysine) but contains omega-3 fatty acids

Question 43

semivegetarian

Answer 43

typically exclude or limit red meat, may also avoid other meats

Question 44

macrobiotic diet

Answer 44

mostly grains, legumes, vegetables; some fruits, nuts, seeds, possibly fish; no meat, eggs, cheese, sugars/sweets, coffee, alcohol, most fruit

Question 45

benefits of vegetarianism

Answer 45

-lower intake of fat and total energy -> decreased risk of overweight and obesity -higher fruit/vegetable intake -> higher antioxidant intake -> decreased CVD risk -lower blood pressure -fewer digestive problems

Question 46

what should vegetarians aim to include in their diet?

Answer 46

complementary proteins, soy products

Question 47

paleolithic diet

Answer 47

high protein, moderate fat & CHO

Question 48

benefits of paleo diet

Answer 48

weight loss, reduced waist circumference, reduced BP, increased insulin sensitivity, improved blood cholesterol

Question 49

ketogenic diet

Answer 49

high fat, low-moderate protein, low CHO; puts the body into ketosis

Question 50

what was the keto diet originally used to treat?

Answer 50

epilepsy

Question 51

benefits of the keto diet

Answer 51

-greater weight loss, lower TGs, lower dBP

Question 52

disadvantages of the keto diet

Answer 52

higher LDL