Amino Acid Metabolism Lecture 2

Front 1

gastric phase digestion (Proton postassium pum in Gastric Parietal Cell)

Back 1

ATP dependent; responsible for acidifying stomach; target of acid reflux drugs

Front 2

pepsinogen (produced in gastric chief cells)

Back 2

autoactivates to become pepsin; autocatalysis from pepsin; cleaves denatured proteins into large peptides and amino acids

Front 3

pyloric sphincter

Back 3

controls influx of aa and peptides into duodenum

Front 4

Pancreatic phase digestion (CCK PZ)

Back 4

cck pz secreted from duodenal endocrine cell

released to the bloodstream, stimulates pancratic zymogens; stimulates the release of enteropeptidases from mucosal cells

Front 5

secritin from the duodenal endocrine cells

Back 5

released to blood stream; stimulates acinar cells to neutralize gastric acid with bicarbonate

Front 6

enteropeptidase

Back 6

cleaves trypsinogen to trypsin; released by duodenal endocrine cell

Front 7

trypsin

Back 7

converts all other pancreatic zymogens; as well as autocatalysis.

Front 8

intestinal digestion

Back 8

small peptides (2-8AA )and amino acids continue into intestine; epithelial cells make and secrete aminopeptidases and dipeptidases; amino acids, di/tri peptides are transported into the epithelial cells

Front 9

protein nutrition (essential amino acids)

Back 9

required for growth, cannot be synthesized by the body

Front 10

non essential amino acids

Back 10

can be synthesized by humans

Front 11

nitrogent balance

Back 11

example: in the absense of an essential amino acids;

incorporation of amino acids into the body is blocked; the breakdown of protein continues so the amount of nitrogen excreted is greater than teh amount of protein digested

Front 12

complete protein

Back 12

source with all the essential amino acids

Front 13

complementary proteins

Back 13

two or more protein sources that provide all essential

Front 14

high quality protein

Back 14

easily digestible/bioavailable complete protein

Front 15

limiting amino acid

Back 15

the essential amino acid that is present in dietary protein in the shortest supply relative tot eh amount needed for the protein synthesis in the body

Front 16

vegetarians

Back 16

vegans only in jeopardy

Front 17

endopeptidases given enough time

Back 17

act as exopeptidases