C - correct answer ✔✔Which of the following curves shows the appropriate relationship between [ES]
and time in steady state kinetics?
(see graphs on #1)
A - correct answer ✔✔Which of the following would represent the reaction coordinate for a two-step
reaction with an initial slow step?
(see graphs on #2)
B - correct answer ✔✔Which of the following amino acids could bind to the specificity pocket of Trypsin?
A) Gly
B) Lys
C) Asp
D) Gln
E) Val
D - correct answer ✔✔The chymotrypsin/trypsin family of proteases has which combination of amino
acids in the active site
A) threonine, histidine, aspartic acid
B) serine, arginine, glutamic acid
C) serine, histidine, glutamic acid
D) serine, histidine, aspartic acid
E) threonine, histidine, aspartic acid
E - correct answer ✔✔Which of the following would be a proper representation of enzyme velocity?
A) v = (-) d[P]/dt
B) v = (+) d[P]/dt
C) v = (-) d[S]/dt
,D) v = (+) d[S]/dt
E) Either B or C
C - correct answer ✔✔The rate constant associated with the reaction below would be 2A --> B
A) Zero order
B) First order
C) Second order
D) Third order
A - correct answer ✔✔Which type of secondary structure present in integral membrane proteins is
readily detectable in the primary structure?
A) membrane-spanning α helix
B) membrane-spanning β sheet
C - correct answer ✔✔Which of the following lipid types are not found in animal membranes?
A) phosphoglycerides
B) cholesterol
C) triacylglycerols
D) glycolipids
E) sphingolipids
C - correct answer ✔✔A molecule moves across a membrane from a lower to a higher concentration
with the aid of a membrane protein. This process is known as:
A) chemiosmotic coupling
B) diffusion
C) active transport
D) facilitated transport
E - correct answer ✔✔Which of the following will cause the opening or closing of a gated ion channel?
,A) pH change
B) phosphorylation
C) voltage change
D) ligand binding
E) all of the above
A - correct answer ✔✔Which amino acid in the aquaporin channel hydrogen bonds with water to
prevent the movement of protons?
A) Asn
B) Leu
C) Phe
D) Val
E) Ile
A - correct answer ✔✔Which of the following second messengers would NOT be found free floating in
the cytosol?
A) DAG
B) Ca2+ ions
C) cAMP
D) IP3
A - correct answer ✔✔Acetylcholine and nicotine competitively bind to nicotinic acetylcholine receptors
to cause the same second messenger activation. Nicotine is considered an _______________ of the
receptors.
A) agonist
B) antagonist
C) repressor
D) activator
, D - correct answer ✔✔The complex formed between a lipid hormone and its receptor binds to _____
which are specific DNA sequences. A) transcription factors
B) nuclear localization sequences
C) DNA-binding domains
D) hormone response elements
E) none of the above
B - correct answer ✔✔Hexokinase undergoes a large conformational change in order to exclude water
from the active site. Would chymotrypsin undergo such a change upon binding its substrate?
A) Yes
B) No
C - correct answer ✔✔In the reaction mechanism of the glycolytic enzyme aldolase, an active site
tyrosine residue accepts a proton from the substrate. In this form the side chain of Tyr must be
_________ and it is acting as a(n) __________ catalyst.
A) protonated; acid
B) deprotonated; acid
C) deprotonated; base
D) protonated; base
E - correct answer ✔✔Based on the reaction below, how would the enzyme catalyzing this reaction be
classified?
(see picture on #17)
A) Oxidoreductase
B) Hydrolase
C) Lyase
D) Ligase
E) Transferase