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Question
ï¢-D-glucopyranose in the chair form is the most widely occurring form of glucose in nature and it has the following characteristics EXCEPT:
a. forms a six-membered ring.
b. carbon 6 is above the plane of the chair.
c. all of the -OH groups are equatorial.
d. the anomeric carbon has a hydroxyl that is below the plane of the chair.
e. all axial positions are occupied by -H.
Answer
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Related questions
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b. Hsp90; un-; chaperonin
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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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c. higher eukaryotic
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Q:
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The linkage between the amino acid and the tRNA in an amino-acyl tRNA complex is:
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Q:
Transcription of a typical gene encoding a polypeptide in eukaryotes involves all of the following EXCEPT:
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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:
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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Q:
All are characteristics of catabolic activator protein (CAP) EXCEPT:
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The base in DNA that specifies the first base in the RNA transcript is called a(n) ____ and is numbered ____.a. promoter; -5b. enhancer; -35c. transcription start site; 0d. transcription start site; +1e. promoter complex; +5
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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
c. a chemical mutagen such as nitrous acid
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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