Review Questions

For each question, choose the ONE BEST answer or completion.

1. A DNA strand of sequence 3' GTCAAGGATATTCGAT 5' would be transcribed in the nucleus to form a polymer of sequence

A. 3' GTCAAGGATATTCGAT 5'.

B. 5' GUCAAGGAUAUUCGAU 3'.

C. 5' CAGUUCCUAUAAGCUA 3'

D. 3' AUCGAAUAUCCUUGAC 5'

2. RNA polymerase from E. coli is a multisubunit protein composed of a, p, p', and a. The promoter sequence is recognized and bound by

3. A rho-independent transcription terminator sequence in prokaryotic DNA has

A. a GC-rich region followed by a string of uracils.

B. a GC-rich region followed by a string of adenines.

C. several stop codons.

D. the sequences TTGACA and TATATT separated by about 17 bases.

E. the sequence AAUAAA and a poly-A tail up to 250 nucleotides long, separated by about 20 bases.

4. The lac operon is transcribed when

A. lactose is present and glucose is absent.

B. cAMP concentrations in the cell are high.

C. The cAMP-CAP protein is bound to the lac promoter region.

D. the lac repressor is bound to allolactose or a similar shaped molecule.

E. all of the above.

5. The trp operon is transcribed when

A. tryptophan concentrations in the cell are high.

B. the trp repressor is bound to tryptophan or a similar shaped molecule.

C. tryptophan is bound to its aporepressor.

D. the appropriate corepressor is absent.

E. all of the above.

6. Before a newly synthesized eukaryotic mRNA attaches to the ribosome, it undergoes

A. capping.

B. polyadenylation.

C. splicing.

D. transport to the cytosol.

E. all of the above.

7. The preinitiation complex of proteins forms at a eukaryotic protein-coding gene promoter in order to

A. align RNA polymerase I.

B. align RNA polymerase II.

C. align RNA polymerase III.

D. align the helicase DnaB.

E. inhibit transcription.

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