BIOC 384 EXAM 2
Which of the THREE following statements about myosin are true? -
ANSWERS-The interaction between myosin and actin converts
chemical energy to mechanical work.
Thick and thin filaments slide past each other during contraction to
shorten the muscle.
Myosin-actin reaction cycle requires hydrolysis of 1 ATP per myosin
head in each cycle.
Refer to the reaction coordinate diagram at right that
compares catalyzed and uncatalyzed reactions. Which of the
following labels are correct? "Activation energy" = AE. - ANSWERS-
3 = Reactant, 1 = DG, 2 = Transition state
Select the most correct statement regarding how catalysts increase
reaction rates. - ANSWERS-Catalysts lower the amount of energy
required to reach the transition state
Choose the five correct labels for the figure to
the right. "Transition State" = TS - ANSWERS-(1) ES (2) TS (3) EP
(4) E + P (5) substrate
, Enzymes increase reaction rates in the following three ways (choose
the BEST answer): - ANSWERS-Provide an alternate path for product
formation, stabilize the transition state, provide optimal environment
Which of the reactions below are examples of reversible
modifications mediated by enzymes. - ANSWERS-Methylation of
cytosine on nucleic acids and phosphorylation of
phosphatidylinositols in the membrane.
Which of the findings below provide support for the transition state
theory of catalysis? - ANSWERS-Transition state analogs bind tightly
to enzyme active sites.
Chymotrypsin is a serine / cysteine protease requiring the formation
of a noncovalent / covalent enzyme
intermediate as a critical step in the reaction. The amino acid residue
serine / histidine has a central role in
general acid-base catalysis at several steps in the reaction mechanism,
which relies on water / phosphate
to generate a nucleophile that attacks a carbonyl carbon. The Gly193
and Asp102 / Ser195 residues are
essential to stabilization of the isotropic / oxyanion intermediate
during the multistep reaction process. - ANSWERS-serine, covalent,
histidine, water, Ser195, oxyanion
What are the THREE key assumptions of Michaelis-Menten kinetics.
- ANSWERS-The reaction is analyzed at a time in the reaction that
negligible product is formed.
Which of the THREE following statements about myosin are true? -
ANSWERS-The interaction between myosin and actin converts
chemical energy to mechanical work.
Thick and thin filaments slide past each other during contraction to
shorten the muscle.
Myosin-actin reaction cycle requires hydrolysis of 1 ATP per myosin
head in each cycle.
Refer to the reaction coordinate diagram at right that
compares catalyzed and uncatalyzed reactions. Which of the
following labels are correct? "Activation energy" = AE. - ANSWERS-
3 = Reactant, 1 = DG, 2 = Transition state
Select the most correct statement regarding how catalysts increase
reaction rates. - ANSWERS-Catalysts lower the amount of energy
required to reach the transition state
Choose the five correct labels for the figure to
the right. "Transition State" = TS - ANSWERS-(1) ES (2) TS (3) EP
(4) E + P (5) substrate
, Enzymes increase reaction rates in the following three ways (choose
the BEST answer): - ANSWERS-Provide an alternate path for product
formation, stabilize the transition state, provide optimal environment
Which of the reactions below are examples of reversible
modifications mediated by enzymes. - ANSWERS-Methylation of
cytosine on nucleic acids and phosphorylation of
phosphatidylinositols in the membrane.
Which of the findings below provide support for the transition state
theory of catalysis? - ANSWERS-Transition state analogs bind tightly
to enzyme active sites.
Chymotrypsin is a serine / cysteine protease requiring the formation
of a noncovalent / covalent enzyme
intermediate as a critical step in the reaction. The amino acid residue
serine / histidine has a central role in
general acid-base catalysis at several steps in the reaction mechanism,
which relies on water / phosphate
to generate a nucleophile that attacks a carbonyl carbon. The Gly193
and Asp102 / Ser195 residues are
essential to stabilization of the isotropic / oxyanion intermediate
during the multistep reaction process. - ANSWERS-serine, covalent,
histidine, water, Ser195, oxyanion
What are the THREE key assumptions of Michaelis-Menten kinetics.
- ANSWERS-The reaction is analyzed at a time in the reaction that
negligible product is formed.
