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Question
The enzyme fumarase has a pH optimum of about 7.6. What would be the buffer of choice to study this enzyme?a. lactic acid (Ka = 1.38 x 10-4, pKa = 3.86)
b. bicarbonate (Ka = 6.3 x 10-11, pKa = 10.24)
c. acetic acid (Ka = 1.74 x 10-5, pKa = 4.76)
d. succinate (Ka = 2.34 x 10-6, pKa = 5.63)
e. tris-hydroxymethyl aminomethane (Ka = 8.32 x 10-9, pKa = 8.07)
Answer
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Related questions
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e. Hsp60; partially; Hsp40
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Q:
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Q:
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Q:
Termination of translation in prokaryotic cells requires:
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b. interaction of release factors with the termination codon.
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Q:
Which of the following does not reqire GTP hydrolysis?
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Q:
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Q:
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Q:
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Q:
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Q:
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Q:
The linkage between the amino acid and the tRNA in an amino-acyl tRNA complex is:
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Q:
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Q:
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Q:
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Q:
The base-pair edges in the ____ groove act as a(n) ____ identifiable through ____ with specific proteins.
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Q:
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Q:
All are correct about enhancer sequences in eukaryotic cells EXCEPT:
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Q:
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Q:
Which of the following would most likely cause a frameshift mutation?
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b. a base analog such as 5-bromouracil
c. a chemical mutagen such as nitrous acid
d. an intercalation agent such as acridine orange
e. none of the above
Q:
Which of the following statements explains why the adenine analog, 2-aminopurine (2-AP), can cause mutations in DNA when it is inserted in place of a site normally occupied by A?
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e. none of the above
Q:
Misincorporation of all subsequent amino acids results from ____ mutations.
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e. all are true
Q:
Mutations in DNA may result from all of the following EXCEPT:
a. spontaneous mutations due to errors in replication.
b. physical insults on the cell, such as UV light.
c. errors in transcription.
d. chemical mutagens.
e. introduction of a base analog into DNA.
Q:
A transition mutation would be replacing A by:
a. T.
b. C.
c. U.
d. G.
e. either T or C