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Question
The initial event in the conversion of an hnRNA to the mature RNA which leaves the nucleus is:a. formation of ribonucleoprotein particles (RNPs).
b. capping the 5'-end of the transcript with a guanylyl group by guanylyl transferase.
c. addition of a poly(A) tail to the 3'-end of the transcript by poly(A) polymerase.
d. splicing together of the exons.
e. transesterification reactions in lariat formation.
Answer
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Related questions
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In general, proteins whose folding is chaperone-dependent start the folding process first with ____ and then are passed as ____ folded intermediates to ____.
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b. Hsp90; un-; chaperonin
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d. Hsp40; partially; Hsp70
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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a. ATP; tRNA terminator; GTP
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Q:
Termination of translation in prokaryotic cells requires:
a. binding of the terminator tRNA to the termination codon.
b. interaction of release factors with the termination codon.
c. ternary interaction of the release factor and the termination tRNA with the termination codon.
d. release factor interaction with the Shine-Dalgarno sequence and subsequent dissociation of the two ribosomal subunits.
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Q:
Which of the following does not reqire GTP hydrolysis?
a. the formation of the initiation complex (translationally active 70 S ribosome complex).
b. the binding of the aminoacyl tRNA to the A site during elongation
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Q:
Which of the following statements is true regarding the formylmethionine that serves as the first amino acid in bacterial protein synthesis?
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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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b. asp; ala; polycationic
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e. arg; lys; polyanionic
Q:
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Q:
All members of a set of tRNAs specific for a particular amino acid - termed ____ tRNA - are served by one ____.
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Q:
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Q:
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d. The code is universally used by virtually all species.
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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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c. allose
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Q:
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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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b. minor; recognition matrix; H-bonding
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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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e. all are true.
Q:
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Q:
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
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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b. 2-AP undergoes oxidative deaminiation to hypoxanthine which basepairs with C
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d. 2-AP is often found as a schiff base that crosslinks with T
e. none of the above
Q:
Misincorporation of all subsequent amino acids results from ____ mutations.
a. chemical
b. base shift
c. frameshift
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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