A bacterial strain has a mutation in the TRP repressor which prevents the protein from ever binding tryptophan. How would you predict this mutation

A bacterial strain has a mutation in the TRP repressor which prevents the protein from ever binding tryptophan. How would you predict this mutation would affect expression of the TRP operon?

AExpression of TRP operon in the presence of tryptophan, but repression in the absence of tryptophan

BRepression of Trp operon in the absence of tryptophan, but expression in the presence of tryptophan

CRepression of the TRP operon in the presence or absence of tryptophan

DExpression of the TRP operon in the presence or absence of tryptophan

EIt is not possible to determine

Which of the following parts of the mature eukaryotic mRNA will not be able to hybridize with the original gene from which they were transcribed ?

AIntron

BCap

Cpoly A tail

DA and B

EAll of the above

RNA polymerase comparsions

Which of the following differentiates prokaryotic RNA polymerase from eukaryotic RNA polymerase II?

ACan transcribe RNA in vitro without additional proteins factors

BCan undergo initial abortive rounds of transcription initiation before promoter clearance

CIs responsible for transcription of all genes of the cell

DA and B

EA and C

Nucleic Acids

Total nucleic acids are extracted from a culture of yeast cells and then mixed with resin beads to which the polynucleotide 5'TTTTTTTTTTTTTTTTTT3' has been covalently attached. After a short incubation with the cellular nucleic acids, the beads are extracted from the mixture. When you analyze the cellular nucleic acids that have stuck to the beads, which of the following will be most abundant?

AtRNA

BmRNA

Cpre-mRNA

DDNA

ErRNA

Translation

It is possible to chemically modify the amino acid cysteine to alanine after it has been covalently attached to a cysteine-tRNA. What would you expect the outcome of this modification when the cysteine charged tRNA is utilized in synthesis of a protein?

AAt an alanine codon, a cysteine amino acid would be incorporated into the growing polypeptide chain

BAt a cysteine codon, a cysteine amino amino would be incorporated into the growing polypeptide

CAt a cysteine codon, an alanine would be incorporated into the growing polypeptide.

DNo change in amino acid incorporation at either cysteine or alanine would occur

EAll of the Above

Translation Initation

What is the most likely outcome of a mutation that introduced an AUG codon twelve nucleotides upstream (5') of the original AUG start codon in a mammalian mRNA?

ANo protein

BNo effect on translation

CTranslation would initiate at the new AUG codon, but the protein product would likely be truncated (shortened) due to a change in reading frame.

DTranslation would initiate at the new AUG codon and the original protein would be synthesized, however, it would have an additional five amino acids added on at the N-terminus.

EAll of the above

Peptide bond formation

Peptide bond formation involves the transfer of the growing polypeptide chain to the N-terminus of the amino acid attached to the A-site tRNA

ATrue

BFalse

RNA basepairing

Which of the following does not directly involve RNA-RNA basepairing to occur?

ASplice site recognition

BTranslation start site selection

CSmall ribosomal subunit recruitment in prokaryotes

DStop Codon recognition