ch 7

Question 1

protein degradation pathways, half lives, g/day

Answer 1

ubiquitin-proteasome, chemical signals - min/hr(regulatory proteins) weeks/months/years (collagen) - 300/400 g/day

Question 2

proteolysis

Answer 2

The hydrolytic cleavage of proteins by proteases, occurs in the stomach and small intestines

Question 3

proteins absorbed at _______

proteins enter blood liver and peripheral tissues at _____

Answer 3

endothelial cells

portal vein

Question 4

protealytic enzymes secreted as

activated by

Answer 4

inactive zymogens(so they don't break down proteins in the cells where they are made and stored)
proteolysis - allows for proper folding of enzyme

Question 5

trypsin

Answer 5

preferentially cleaves peptide bonds between hydrophobic amino acids and aromatic amino acids

Question 6

chymotrypsin

Answer 6

preferentially cleaves peptide bonds after an aromatic amino acid

Question 7

elastase

Answer 7

cuts after amino acids with smaller, hydrophobic side chains such as gly, ala