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Question
All of the following statements about nucleotides are true EXCEPT:a. They are produced by nearly all organisms.
b. The rate of proliferation of a cell can determine the amount of DNA and RNA synthesized per unit of time.
c. Uridine nucleotide derivatives of carbohydrates are common intermediates in cellular transformation of carbohydrates.
d. Many coenzymes are derivatives of nucleotides.
e. The nitrogenous bases serve as energy sources.
Answer
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e. Hsp60; partially; Hsp40
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In a class I aminoacyl-tRNA synthetase, which of the following reacts with the acyl phosphate formed during the reaction of ATP with the amino acid?a. 5'-hydroxyl of the nucleotide on the 5' end of the tRNA moleculeb. 3'-hydroxyl of the nucleotide on the 5' end of the tRNA moleculec. 2'-hydroxyl of the nucleotide on the 5' end of the tRNA moleculed. 3'-hydroxyl of the nucleotide on the 3' end of the tRNA moleculee. 2'-hydroxyl of the nucleotide on the 3' end of the tRNA molecule
Q:
Each of the following statements regarding ways in which eukaryotic protein synthesis differs from prokaryotic protein synthesis is true EXCEPT:
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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.
c. ternary interaction of the release factor and the termination tRNA with the termination codon.
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Q:
Which of the following does not reqire GTP hydrolysis?
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Q:
Mitochondrial and chloroplastic ribosomes resemble ____ ribosomes.
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b. lower eukaryotic
c. higher eukaryotic
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Q:
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Q:
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The base-pair edges in the ____ groove act as a(n) ____ identifiable through ____ with specific proteins.
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The eukaryotic transcription factor that exhibits a sequence specificity for the TATA box is:
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Q:
All are correct about enhancer sequences in eukaryotic cells EXCEPT:
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All are characteristics of catabolic activator protein (CAP) EXCEPT:
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Which of the following would most likely cause a frameshift mutation?
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b. a base analog such as 5-bromouracil
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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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Q:
Misincorporation of all subsequent amino acids results from ____ mutations.
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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