Chapter 6 Protein Flashcards
how do the amino acids differ?
they each have a different side chain
essential AA are provided through
the foods that we eat
how do to get non-essential AA ?
we make them is we have enough AA to provide the raw materials
how many essential amino acids are there?
9
how many amino acids are there?
20
protein digestion in mouth
nothing
protein digestion in stomach
acids denature proteins. or in other word they break them down to straight chains of AA . the AA are then cleaved into polypeptides and some AA.
protein digestion in small intestine
enzymes from the pancreas and the intestine split peptide strands into tripeptides, dipeptides and AA. The enzymes on the surface of the small intestine wall then break down the peptides further into AA which are then carried into the blood stream
AA in the bloodstream
from the blood stream they are then transported to all the body’s cells.
protein are _____ functional once denatured
Proteins are no longer functional once denatured
what are the roles of protein in the body?
structure and movement growth and maintenance build enzymes, hormones, and other compounds antibodies transport fluid and electrolyte balance acide base balance blood clotting energy and glucose
what does the fate of and AA depend on?
the needs of the cells
what are some potential fates of an AA?
they can be used to build another protein or another N-containing compound of they can be dismantled
What are some uses of a dismantled amino acid?
use N to make a different non essential AA or
excrete N and use the residue for energy
what happens to the amino group of an AA?
it is removed when the AA is used for energy and converted to urea which is excreted in the urine
what happens to the acid and side chain when an AA is used for energy?
it is metabolized like carb or fat
what does it mean to waste a protein?
it means that the protein is not being used for its unique fucntions
When is protein wasted?
when there is too little energy from glucose, Fatty acids
when diet provides more protein than the body needs
when supplements cause the body to have an excess of a single AA
when dietary protein is low quality with too few essential AA
positive nitrogen balance
when you excrete less nitrogen than you ingest
ex: weight lifting, pregnant, growing
negative nitrogen balance
when you excrete more nitrogen than you ingest
ex: astronauts, bedridden patients
nitrogen balance
when you excrete as much nitrogen as you ingest
ex: healthy people
what foods and food groups provide the most protein?
meats/protein provide the most protein
how well does following choose my plate (CMP) recommendations provide protein?
its greater than the RDA and AMDR
what percent of calories come from protein by following the CMP recommendations?
18% or a 2000 cal diet and 16% for a 3000 diet
High quality proteins
they have enough of all the essential AA for the body to make its own working proteins
high quality proteins come from:
animal sources
mid range quality proteins come from:
legumes
lower quality proteins come from:
grains
complementary proteins
two or more proteins whose amino acid assortments complement each other in such a way that the essential amino acids missing from one are supplied by the other
what are some examples of complementary proteins?
tortillas and beans
rice and lentils
pita bread and hummus (beans)
bread and peanut butter
what is the RDA for protein?
0.8 g/kg of your healthy body weight
how do you calculate your protein RDA?
weight in kg X (0.8g/kg)
how many pounds in a kilogram?
2.2
AMDR for protein
10-35%
What about High protein/low carb diets?
they effect other food and nutrients by excluding important sources of some nutrients.
it doesn’t support work and exercise because you needs carbs to efficiently burn calories
you need to increase fluids
the cost isn’t worth it
there are possible links to health problems in the colon
what happens when you have too little protein?
slow growth in children
impaired brain and kidney function
weakened immune defense
impaired nutrient absorption
what are some deficiencies that arise from low protein and calorie intake?
iron zinc vit B12 niacin calcium
what are some consequences to low protein and calorie that are related to function?
muscle and bone atrophy antibodies are not there fluid imbalance which causes edema working cells in organs apathetic and listless
what happens to your kidneys when you have too much protein?
it causes extra work for the kidney which becomes a problem when protein intake is excessive and if a person has kidney disease
Cancer and heart disease are moderately linked to which sources of protein?
high intake of red meats ( beef, lamb, pork) and processed meats (lunch meats, hot dogs)
Do athletes need extra protein?
no there is insufficient evidence
muscle growth is stimulated by exercise not protein intake
purified AA supplements and extra protein for body builders is generally_____
not useful
Celiac Disease
Autoimmune response to protein in wheat, barley, and rye
what happens to your villi in celiac disease
they are flattened and destroyed, reducing nutrient absorption
What are symptoms of celiac disease?
poor growth
weight loss due to malabsorption
what is the treatment for celiac diseases?
avoid gluten for the rest of your life
many gluten-free options available
