Micro Ch. 8

24) An enzyme that copies DNA to make a molecule of RNA is A) RNA polymerase. B) DNA ligase. C) DNA helicase. D) transposase. E) DNA polymerase.

A) RNA polymerase.

5) Which of the following is NOT a product of transcription? A) a new strand of DNA B) rRNA C) tRNA D) mRNA E) None of the answers are correct; all of these are products of transcription.

A) a new strand of DNA

12) In Figure 8.2, if base 4 is thymine, what is base 4'? A) adenine B) thymine C) cytosine D) guanine E) uracil

A) adenine

21) The mechanism by which the presence of glucose inhibits the lac operon is A) catabolite repression. B) translation. C) DNA polymerase. D) repression. E) induction.

A) catabolite repression.

6) An enzyme produced in response to the presence of a substrate is called a(n) A) inducible enzyme. B) repressible enzyme. C) restriction enzyme. D) operator. E) promoter.

A) inducible enzyme.

22) If you knew the sequence of nucleotides within a gene, which one of the following could you determine with the most accuracy? A) the primary structure of the protein B) the secondary structure of the protein C) the tertiary structure of the protein D) the quaternary structure of the protein E) The answer cannot be determined based on the information provided.

A) the primary structure of the protein

16) Refer to Table 8.2. If the sequence of amino acids encoded by a strand of DNA is serine-alanine-lysine-leucine, what is the order of bases in the sense strand of DNA? A) 3' UGUGCAAAGUUA B) 3' AGACGTTTCAAT C) 3' TCTCGTTTGTTA D) 5' TGTGCTTTCTTA E) 5' AGAGCTTTGAAT

B) 3' AGACGTTTCAAT

17) Refer to Table 8.2. If the sequence of amino acids encoded by a strand of DNA is serine-alanine-lysine-leucine, the coding for the antisense strand of DNA is A) 5' ACAGTTTCAAT. B) 5' TCTGCAAAGTTA. C) 3' UGUGCAAAGUUA. D) 3' UCUCGAAAGUUA. E) 3' TCACGUUUCAAU.

B) 5' TCTGCAAAGTTA.

23) An enzyme that makes covalent bonds between the sugar of one nucleotide and the phosphate groups in another nucleotide in DNA is A) RNA polymerase. B) DNA ligase C) DNA helicase. D) transposase. E) DNA polymerase.

B) DNA ligase

2) Which of the following pairs is mismatched? A) DNA polymerase — makes a molecule of DNA from a DNA template B) RNA polymerase — makes a molecule of RNA from an RNA template C) DNA ligase — joins segments of DNA D) transposase — insertion of DNA segments into DNA E) DNA gyrase — coils and twists DNA

B) RNA polymerase — makes a molecule of RNA from an RNA template

7) Transformation is the transfer of DNA from a donor to a recipient cell A) by a bacteriophage. B) as naked DNA in solution. C) by cell-to-cell contact. D) by crossing over. E) by sexual reproduction.

B) as naked DNA in solution.

13) In Figure above, if base 4 is thymine, what is base 11' (remember the complimentary configuration of bases in DNA)? A) adenine B) thymine C) cytosine D) guanine E) uracil

B) thymine

1) A gene is best defined as A) any random segment of DNA. B) three nucleotides that code for an amino acid. C) a sequence of nucleotides in DNA that codes for a functional product. D) a sequence of nucleotides in RNA that codes for a functional product. E) the RNA product of a transcribed section of DNA.

C) a sequence of nucleotides in DNA that codes for a functional product.

14) In Figure above, base 2 (and ONLY the base) is covalently bound/attached to A) ribose. B) phosphate. C) deoxyribose. D) thymine. E) The answer cannot be determined based on the information provided.

C) deoxyribose.

20) Conjugation differs from reproduction because conjugation A) replicates DNA. B) transfers DNA vertically, to new cells. C) transfers DNA horizontally, to nearby cells without those cells undergoing replication. D) transcribes DNA to RNA. E) copies RNA to make DNA.

C) transfers DNA horizontally, to nearby cells without those cells undergoing replication.

4) DNA is constructed of A) a single strand of nucleotides with internal hydrogen bonding. B) two complementary strands of nucleotides bonded A—C and G—T. C) two strands of nucleotides running in an antiparallel configuration. D) two strands of identical nucleotides in a parallel configuration with hydrogen bonds between them. E) None of the answers is correct.

C) two strands of nucleotides running in an antiparallel configuration.

18) Refer to Table 8.2 The anticodon for valine is A) GUU. B) CUU. C) CTT. D) CAA. E) GTA.

D) CAA.

3) Which of the following statements is FALSE? A) DNA polymerase joins nucleotides in one direction (5' to 3') only. B) The leading strand of DNA is made continuously. C) The lagging strand of DNA is started by an RNA primer. D) DNA replication proceeds in only one direction around the bacterial chromosome. E) Multiple replication forks are possible on a bacterial chromosome.

D) DNA replication proceeds in only one direction around the bacterial chromosome.

19) Refer to Table 8.2. What is the sequence of amino acids encoded by the following sequence of bases in a strand of DNA (pay attention to the polarity of the DNA here)? 3' ATTACGCTTTGC A) leucine-arginine-lysine-alanine B) asparagine-arginine-lysine-alanine C) asparagine-cysteine-valine-serine D) Translation would stop at the first codon. E) The answer cannot be determined based on the information provided.

D) Translation would stop at the first codon.

15) The damage caused by ultraviolet radiation is A) never repaired. B) repaired during transcription. C) repaired during translation. D) cut out and replaced. E) repaired by DNA replication.

D) cut out and replaced.

In Figure 8.5, which model of the lac operon correctly shows RNA polymerase, lactose, and repressor protein when the structural genes are being transcribed? A) a B) b C) c D) d E) e

D) d

25) The cancer gene ras produces mRNA containing an extra exon that includes a number of UAA codons. Cancer cells produce ras mRNA missing this exon. This mistake most likely is due to a mistake by A) a chemical mutagen. B) DNA polymerase. C) photolyases. D) snRNPs. E) UV radiation.

D) snRNPs.

8) Genetic change in bacteria can be brought about by A) mutation. B) conjugation. C) transduction. D) transformation. E) All of the answers are correct.

E) All of the answers are correct.

28) Protein synthesis in eukaryotes is similar to the process in prokaryotes in that both eukaryotes and prokaryotes A) have exons. B) have introns. C) require snRNPS. D) use methionine as the "start" amino acid. E) use codons to determine polypeptide sequences.

E) use codons to determine polypeptide sequences.

10) Cell-to-cell contact is required for transduction to occur.

False

3) Bacteria typically contain multiple chromosomes.

False

5) The miRNAs in a cell inhibit protein synthesis by forming complementary bonds with rRNA.

False

6) Some cells may contain multiple genomes.

False

9) Transposition (insertion of a transposon into a DNA sequence) results in the formation of base substitution mutations in a cell's DNA.

False

1) Recombination will always alter a cell's genotype

True

2) Open-reading frames are segments of DNA in which both start and stop codons are found.

True

4) Mutations that are harmful to cells occur more frequently than those that benefit cells.

True

7) Both base substitution and frameshift mutations can result in the formation of premature stop codons.

True

8) In the Ames test, any colonies that form on the control should be the result of spontaneous mutations.

True