Chapter 8 Microbial Genetics
8.1 Multiple Choice Questions
1) A gene is best defined as
A) a 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) a transcribed unit of DNA.
Answer: C
Skill: Recall
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
Answer: B
Skill: Recall
3) Which of the following statements is FALSE?
A) DNA polymerase joins nucleotides in one direction 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 one direction around the bacterial chromosome.
E) Multiple replication forks are possible on a bacterial chromosome.
Answer: D
Skill: Understanding
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 antiparallel.
D) two strands of identical nucleotides with hydrogen bonds between them.
E) None of the answers is correct.
Answer: C
Skill: Understanding
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.
Answer: A
Skill: Understanding
6) Which of the following statements about bacteriocins is FALSE?
A) The genes coding for them are on plasmids.
B) They cause food-poisoning symptoms.
C) Nisin is a bacteriocin used as a food preservative.
D) They can be used