METABOLISM OF PROTEINS Flashcards
the body’s digestive system breaks down protein into the ____
individual amino acids
amino acids are absorbed and used by cells to ____ and a few other macromolecules, such as DNA
build other proteins
a good dietary source of protein
eggs
one egg, whether raw, hard-boiled, scrambled, or fried supplies about ____g of protein
6g
first step in egg digestion
chewing
PROCESSES
mouth to stomach
chew
mechanical breakdown
salivary glands -> swallowing
partially mashed tru esophagus
mashed enter stomach trhu esophageal sphincter
PROCESSES | MOUTH TO STOMACH
provide saliva to aid in swallowing
salivary glands
PROCESSES | MOUTH TO STOMACH
partially mashed egg pass thru
esophagus
PROCESSES | MOUTH TO STOMACH
mashed egg enter stomach thru
esophageal sphincter
stomach releases gastric juices containing ____ and ____, which initiate the breakdown of the protein
HCl and pepsin
the acidity of the stomach facilitates the ____ that still retain part of their 3D structure after cooking
unfolding of the proteins
the acidity of the stomach helps ____ formed during cooking
break down the protein aggregates
where does the break down of protein starts
stomach
- secreted by the chief cells of the stomach
- dismantles the protein chains into smaller and smaller fragments
pepsin
pepsin are secreted by the ____ of the stomach
chief cells
____ is secreted by the parietal cells of the stomach
HCl
HCl is secreted by the ____ of the stomach
parietal cells
egg proteins are large globular molecules and their chemical breakdown requires ____ and ____
time & mixing
the powerful mechanical stomach contractions churn the partially digested protein into a more uniform mixture called
chyme
protein digestion in the stomach takes ____ than carbohydrate digestion
longer time
protein digestion in the stomach takes a ____ than fat digestion
shorter time
eating a ____ increases the amount of time required to sufficiently break down the meal in the stomach
high protein meal
METABOLISM OF PROTEINS
food remains in the stomach ____
longer
ENZYMES INVOLVED
Pancreatic juice
trypsin
chymotrypsin
carboxypeptidase
ENZYMES INVOLVED
Intestinal mucosal cells
aminopeptidase
all enzymes involved in protein digestion are
proteolytic enzymes
amino acids are transported from intestinal lumen to the blood
distal duodenum to proximal jejunum
the absorption of proteins / entry of proteins into the blood vessels require
active transport and ATP
once the amino acids are in the blood, they are transported to the
liver
____ makes it to the large intestine if you are not eating excessive amounts
very little protein
a sign that you are eating **too much protein **
smelly flatulence
all proteins are absorded as
tripeptides
dipeptides
amino acids
the peptides and/or amino acids pass through the interstitial brush border by ____ or ____
facilitative diffusion or active trasnport
determines the type of transporter used
R group
once passed thru the membrane, the amino acids or peptides are released into the intestinal blood stream and are transported to the liver by the ____
hepatic portal vein
in the liver, ____% remain and are used to synthesize protein, nitrogen containing compounds and form purine/pyrimidine bases
50-65%
