Question :
11.Which of the following correctly describes pepsinogen?
A) It the inactive : 1318501
11.Which of the following correctly describes pepsinogen?
A) It is the inactive form of the enzyme pepsin.
B) It is the cofactor for the enzyme pepsin.
C) It is the inhibitor of the enzyme pepsin.
D) It is an isoenzyme of pepsin.
E) It is the name of the reaction catalyzed by pepsin.
12.Which of the following best describes the type of binding between an irreversible inhibitor and an enzyme?
A) weak
B) non-covalent
C) hydrogen bonding
D) hydrophobic interactions
E) very tight
13.Acetylcholine is a neurotransmitter that transmits a signal from a nerve cell to a muscle cell, causing the muscle to contract. How is the neurotransmitter inactivated so that the muscle can relax?
A) It is denatured by the local pH and loses its active conformation.
B) It is hydrolyzed by the enzyme acetylcholinesterase.
C) It is taken up and stored by the muscle cells.
D) It is dissolved in the blood and is transported through the circulatory system.
E) All of the above.
14.The enzyme acetylcholinesterase catalyzes the hydrolysis of acetylcholine. Which of the following is a product of this hydrolysis reaction?
A)
B)
C)
D)
E)
15.Proteases, or proteolytic enzymes, are responsible for which of the following functions?
A) formation of the zwitterion form of a protein
B) hydrolysis of the ester bonds in dietary triglycerides
C) hydrolysis of the peptide bonds between amino acids in proteins
D) formation of the glycosidic linkages in disaccharides and polysaccharides
E) formation of bacterial cell walls
16.What three structurally similar pancreatic serine proteases function to cleave certain peptide bonds in proteins?
A) pepsinogen, zymogen, and acetylcholinesterase
B) pepsinogen, trypsin, and pepsin
C) tryptophan, trypsin, and chymotrypsin
D) trypsin, chymotrypsin, and elastase
E) choline, tryptophan, and proline
17.The protease enzyme chymotrypsin cleaves peptide bonds on the carbonyl side of aromatic amino acids. Which labeled bond in the peptide below would be cleaved by chymotrypsin?
A) A
B) B
C) C
D) D
E) E
18.Elastase is a protease enzyme that cleaves peptide bonds on the carbonyl side of the amino acids glycine and alanine. What products result from treatment of a peptide with the primary structure shown below with elastase?
Pro-Gly-Phe-Ala
A) the individual amino acids proline, glycine, phenylalanine, and alanine
B) Pro-Gly, phenylalanine, and alanine
C) proline, Gly-Phe, and alanine
D) Pro-Gly, and Phe-Ala
E) proline, glycine, and Phe-Ala
19.Trypsin is a protease enzyme that cleaves peptide bonds on the carbonyl side of basic amino acids. Which labeled bond(s) in the peptide below would be cleaved by trypsin?
A) A
B) B
C) C
D) D
E) A, C, and D
20.About half of the 223 amino acids in the enzyme trypsin are hydrophobic. Where in the tertiary structure of this globular protein are these amino acids most likely to be found?
A) at the N-terminal end of the protein chain
B) at the C-terminal end of the protein chain
C) on the exterior surface of the folded protein
D) in the interior of the folded protein
E) in the active site of the enzyme
