nutrition exam 2

what is the role of protein?

growth and repair, overall maintenance in body

what is the key structural difference between CHO and fat and proteins?

protein has nitrogen

what happens if nitrogen is taken off a protein and not picked up?

turns into free ammonia in blood which is toxic

what is the structure of amino acids?

a central carbon, nitrogen amine group, and acid on other end

how many amino acids are needed to make proteins in the body?

20; 9 essential and 11 nonessential

what are the linkages between proteins called?

peptide bonds

what is an r group?

any group attached to carbon or hydrogen

how many different r groups are there?

20 different r groups; 20 different amino acids

what is the function of an r group?

gives character, shape, and function for AA

what happens if you do not have all 9 essential amino acids?

you do not make proteins

what are the two semi-essential amino acids?

cystine and tyrosine

what is an incomplete protein?

missing one or more of the essential amino acids; cannot build a protein

what is a limiting amino acid?

the missing essential amino acid on an incomplete protein

what groups of foods are used to complement proteins?

grains, seeds, peanuts, legumes

what has no source of protein?

veggies

what are 2 exceptions to incomplete proteins?

soybean and quinoa

what does transamination do?

makes nonessential amino acids by transferring the amine group to a carbon skeleton to form a new nonessential amino acid

what B vitamin is needed for transamination reactions?

B6

what are the 3 major transaminations and where found?

aspartame (heart)
alanine (liver and kidney)
branch chained amino acids (muscles)

what type of protein is found in north american diet?

animal (primarily beef)

what protein source is predominate worldwide?

rice

what is meant by biological value?

how fast the protein can get turned into human tissue/muscle

what protein has the highest biological value?

egg whites

what are some roles/functions of protein

build and repair tissue
hormones
digestive enzymes
forming antibodies
pH balance
fluid balance

what is protein sparing?

using carbohydrates rather than protein as an energy source

what happens if you are not eating enough carbohydrates?

protein would be shifted towards energy production and not doing maintenance stuff

what does the body want from protein?

the amino acids

where do amino acids go after digestion?

into pools throughout body (muscle, heart, blood, brain)

do the pools get bigger if you consume more protein?

no they are finite

what is anabolic?

building up

what is catabolic?

breaking down (not consuming enough carbs and therefore using proteins as an energy source)

what must be taken off of protein when it is used as an energy source?

nitrogen

where is excess protein stored?

as fat

what is the recommended protein consumption post exercise?

10-20 grams

what type of protein should be consumed post exercise?

any complete (soybean, meat, dairy)

what amino acid turns on muscle protein synthesis?

leucine (one of 3 branched chained amino acids)

what are positive factors that influence mTOR pathway?

leucine, eating (insulin)

what are negative factors that influence mTOR pathway?

alcohol, stress, lack of sleep

what is the recommended intake of protein per kg of bodyweight?

0.8 grams

how do you calculate recommended intake for protein?

weight (lbs)/ 2.2 = kg/bw, then multiply by 0.8

what is the AMDR for protein?

10-35% of total calories

what are the two diseases associated with protein malnutrition?

Kwashiorkor and Marasmus

what is Kwashiorkor?

protein deficiency because second child is born and first child is weaned from breast milk onto an incomplete protein

what is Marasmus?

starvation, not getting enough to eat, result to using protein as an energy source

what is the difference between fats and oils?

fats are solid at room temp and oils are liquid at room temp

what should fats and oils be called?

lipids

what is the ratio of oxygen to carbon in fats compared to protein and CHO

lower ratio of oxygen in fats (much higher hydrogen ratio)

what happens when fats and oils are mixed with water?

they do not dissolve or mix, fat floats to top of water in hydrophobic solution

what are the three classifications of lipids?

triglycerides, phospholipids, sterols

what is the structure of triglycerides?

glycerol backbone and 2 FA

what form do we store fat in?

triglycerides

what form of fat do we eat the most?

triglycerides (95%)

how do we name FA?

where the double bond is determines name (count in to double bond)

how can FA differ from one another?

degree of saturation, number of bonds, chain length

what are the 3 types of FA?

saturated, monounsaturated, polyunsaturated

what is a saturated FA?

no double bonds, higher cholesterol, solid at room temp, mostly from animals

what is a monounsaturated FA?

one double bond, lowers cholesterol, liquid at room temp, mostly from plants

what is a polyunsaturated FA?

multiple double bonds, lowers cholesterol, liquid at room temp, mostly from plants

what are the two oils that are the exception to the rules on polyunsaturated fats?

coconut and palm oils

what is a hydrogenated fat?

the fat that has had hydrogen added to its double bonds, making it more solid

what does cis mean?

same side

what does trans mean?

different sides

what do trans fatty acids do to LDL and HDL?

raise LDL and lower HDL

what do trans fatty acids do to cholesterol?

raise cholesterol

where do fats go in the body first?

lymphatic system

what is LDL composed mainly of?

chylomicrons

what is HDL composed mainly of?

protein

how do you identify a heart healthy margarine?

whatever liquid is first

how do you identify a heart healthy peanut butter?

oil on top

what is the structure of a phospholipid?

phosphate group and two fatty acids

what do phospholipids do?

emulsify fats

what is a type of a phospholipid?

lecithin

what is the structure of a sterol?

big ringed structure

what are examples of sterols?

cholesterol, testosterone, progesterone, Vitamin D

what is desirable blood cholesterol?

200 or below

what is high risk blood cholesterol?

240 and above

what level do you want HDL to be at?

40 and above

what happens if HDL is above 60?

you have a protective effect against heart disease

what level do you want LDL to be?

less than 100, 130 and above is bad, 190 is great risk

how do you increase HDL?

exercise and moderate alcohol

how do you decrease LDL?

exercise and monounsaturated fats

what are the two essential fatty acids

omega 3 and omega 6

what does omega 3 do?

decrease blood clots, vasodilators, decrease cardiovascular disease

what does omega 6 do?

increase blood clots, vasocontrict, raise blood pressure and chance of cardiovascular disease

does omega 3 or omega 6 have a longer name?

omega 3 has a longer name

what is a food source of omega 3?

cold water fish (from the algae)

what fatty acid do Americans eat more of?

omega 6

what happens if you consume too much omega 3 fatty acid?

unable to form blood clots

what is a chylomicron made mostly of?

mostly triglycerides

what is a chylomicron remnant made of?

mostly triglycerides, just less than original

where does VLDL come from, what is it made of?

comes from liver, triglycerides and B100

what is IDL made of?

mostly triglycerides and B100

what is LDL made of?

mostly cholesterol and B100

what pathway has no down regulation and what occurs because of this?

chylomicron pathway, eventually will lead to a heart attack as plaque builds up

where does a B48 apoprotein come from?

gut

where does a B100 apoprotein come from?

liver

what is the AMDR recommendations for fat in the diet?

20-35%

what are the characteristics of the mediterranean diet?

olive oil, lots of fruit and veggies, less saturated fat, more dairy, moderate alcohol

where does protein digestion begin?

in stomach

what is a bolus?

ball of chewed up food