BCHM 307 Final Exam Questions with Verified Answers – Biochemistry & Molecular Biology

BCHM 307 Final Exam/ Actual Exam Questions with Correct x x x x x x x x




Verified Answers- Latest Update 2025 – Rated A+ x x x x x x x x




Which of the following describes the isomerization of citrate to isocitrate? - ANSWER - converts a tertiary
x x x x x x x x x x x x x x x x



alcohol, which cannot easily be oxidized, to a secondary alcohol that can be oxidized
x x x x x x x x x x x x x x




What is the purpose of DNA helicase? - ANSWER - separation of double stranded DNA into single stranded
x x x x x x x x x x x x x x x x x



DNA in front of DNA polymerase
x x x x x x




Which of the following mutations would cause a bulge in the DNA backbone? - ANSWER - transversion
x x x x x x x x x x x x x x x x



mutation
x




What is the nucleophile in the DNA polymerase mechanism? - ANSWER - the 3' hydroxyl on the
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deoxyribose
x




During the first half of the chymotrypsin mechanism where the acyl-enzyme intermediate is formed,
x x x x x x x x x x x x x



what role does His play? - ANSWER - general base then general acid
x x x x x x x x x x x x x




How many cytochrome c molecules are oxidized by Complex IV for each molecule of oxygen that is
x x x x x x x x x x x x x x x x



reduced - ANSWER - 4
x x x x x




Which of the following occurs when the catalytic subunit of ATP synthase is in the loose state? - ANSWER
x x x x x x x x x x x x x x x x x x



- ADP and Pi bind
x x x x




Why is the occasional production of the superoxide radical anion by complex IV of the electron transport
x x x x x x x x x x x x x x x x



chain problematic? - ANSWER - It is highly reactive and can damage nearby biomolecules.
x x x x x x x x x x x x x x




Which of the following can happen when a photosynthetic pigment absorbs light? - ANSWER - energy is
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lost as heat
x x x




pg. 1
x

,b. energy is given of f as fluorescence
x x x x x x x




c. exciton transfer to a neighboring pigment
x x x x x x




If the reduction potential for NAD+ is -0.315 V and the reduction potential for oxygen is 0.815 V, what is
x x x x x x x x x x x x x x x x x x x



the potential for the oxidation of NADH by oxygen? - ANSWER - 1.13 V
x x x x x x x x x x x x x x




Which of the following transport systems is used in the inner mitochondrial membrane? IMS =
x x x x x x x x x x x x x x



intermembrane space - ANSWER - antiport of ADP from IMS to matrix and of ATP from matrix to IMS
x x x x x x x x x x x x x x x x x x




The highest point in a reaction coordinate diagram represents
x x x x x x x x x . - ANSWER - the transition state
x x x x x x




Of the following ions, which would be most likely to participate in metal ion catalysis? - ANSWER - Zn2+
x x x x x x x x x x x x x x x x x x




An organic molecule that is tightly bound to an enzyme and participates in an enzyme catalyzed reaction
x x x x x x x x x x x x x x x x



is specifically referred to as a
x x . - ANSWER - prosthetic group x x x x x x x x x x




Which of the following amino acids would be most likely found in the active site of an enzyme that uses
x x x x x x x x x x x x x x x x x x x



acid-base catalysis? - ANSWER - His
x x x x x x




The ability for an enzyme to pick out one particular substrate from the myriad of molecules floating
x x x x x x x x x x x x x x x x



around its environment is an example of
x . - ANSWER - specificity
x x x x x x x x x x x




How does a catalyst affect the overall deltaG of an endergonic reaction? - ANSWER - it has no effect
x x x x x x x x x x x x x x x x x x




Which of the following is the most effective way to increase the rate of a biochemical reaction? - ANSWER
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- add a catalyst
x x x x




How does a catalyst increase the rate of a reaction? - ANSWER - it allows reacting molecules to more
x x x x x x x x x x x x x x x x x x



easily form the transition state
x x x x x




Of all the species that enzymes bind, they are thought to bind most tightly to
x x x x x x x x x x x x x x x . - ANSWER -
x x x



transition states
x x




pg. 2 x

, Chymotrypsin catalyzes the hydrolysis of a peptide bond and is therefore categorized as a
x x x x x x x x x x x x x x .- x



ANSWER - hydrolase
x x x




Chymotrypsin has a large specificity pocket to bind the aromatic amino acids while elastase has a very
x x x x x x x x x x x x x x x x



small specificity pocket meant to bind Ala or Gly. Which of the following amino acid substitutions
x x x x x x x x x x x x x x x x



changes the specificity pocket of chymotrypsin to that of elastase? (Try to figure this out based on amino
x x x x x x x x x x x x x x x x x



acid structures rather than just looking it up!) - ANSWER - Gly -> Val
x x x x x x x x x x x x x x




If the Asp in the chymotrypsin active site was mutated to another amino acid, which of the following
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would be considered an invisible mutation in that it is least likely to impact the function of the enzyme? -
x x x x x x x x x x x x x x x x x x x x



ANSWER - Asp → Glu
x x x x x




Zymogens are not enzymatically active because x x x x x x . - ANSWER - their active sites are distorted and
x x x x x x x x x



incapable of enzymatic activity
x x x x




The molecule chymotrypsinogen is known as a(n)
x x x x x x x . - ANSWER - zymogen
x x x x




What three amino acids are found in the catalytic triad of chymotrypsin? - ANSWER - Asp, His, Ser
x x x x x x x x x x x x x x x x x




Conversion of factor X to factor Xa represents a(n) form of activation; binding of antithrombin to
x x x x x x x x x x x x x x x



thrombin represents a(n)
x form of inhibition. - ANSWER - irreversible; reversible
x x x x x x x x x x




An enzyme that forms a covalent bond with its substrate during the course of a reaction is considered to
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undergo
x . - ANSWER - covalent catalysis
x x x x x x




Which protein in the blood is responsible for converting fibrinogen to fibrin? - ANSWER - thrombin
x x x x x x x x x x x x x x x




Different enzymes that catalyze the same reaction are known as
x x x x x x x x x x . - ANSWER - isoenzymes
x x x x




In an enzyme mechanism that generates a negative charge in the transition state, which of the following
x x x x x x x x x x x x x x x x



would be most effective to have in the active site of the enzyme? - ANSWER - transition metal cation
x x x x x x x x x x x x x x x x x x x




pg. 3 x