Microbiology Chapter 8 Test Bank
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. - ANSa sequence of nucleotides in DNA
that codes for a functional product.
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 - ANSrRNA
In Figure 8.1, which colonies are streptomycin-resistant and leucine-requiring? - ANS4 and 8
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 - ANSRNA polymerase - makes a molecule of RNA from
an RNA template
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. - ANSDNA replication
proceeds in only one direction around the bacterial chromosome
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 - ANStwo strands of nucleotides running in an antiparallel
configuration
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 to identify certain bacteria.
E) Bacteriocins kill bacteria. - ANSthey cause food-poisoning symptoms
Culture 1: F+, leucine+, histidine+
Culture 2: F-, leucine-, histidine-
8) In Table 8.1, what will be the result of conjugation between cultures 1 and 2 (reminder: F+
has a different meaning than Hfr)?
A) 1 will remain the same;
2 will become F+, leucine-, histidine-
B) 1 will become F-, leu+, his+;
2 will become F+, leu-, his-
C) 1 will become F-, leu-, his-;
2 will remain the same
D) 1 will remain the same;
2 will become F+, leu+, his+
E) 1 will remain the same;
2 will become F+ and recombina - ANS1 will remain the same; 2 will become F+, leucine-,
histidine-
In Table 8.1, if culture 1 mutates to Hfr, what will be the result of conjugation between the two
cultures?
A) They will both remain the same.
B) 1 will become F+, leu+, his+;
2 will become F+, leu+, his+
C) 1 will remain the same;
recombination will occur in 2
D) 1 will become F-, leu+, his+;
2 will become Hfr, leu+, his+
E) The answer cannot be determined based on the information provided. - ANS1 will remain the
same; recombination will occur in 2
Which of the following statements regarding a bacterium that is R+ is FALSE?
A) It possesses a plasmid.
B) R+ can be transferred to a cell of the same species.
C) It is resistant to certain drugs and heavy metals.
D) It is F+.
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. - ANSa sequence of nucleotides in DNA
that codes for a functional product.
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 - ANSrRNA
In Figure 8.1, which colonies are streptomycin-resistant and leucine-requiring? - ANS4 and 8
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 - ANSRNA polymerase - makes a molecule of RNA from
an RNA template
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. - ANSDNA replication
proceeds in only one direction around the bacterial chromosome
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 - ANStwo strands of nucleotides running in an antiparallel
configuration
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 to identify certain bacteria.
E) Bacteriocins kill bacteria. - ANSthey cause food-poisoning symptoms
Culture 1: F+, leucine+, histidine+
Culture 2: F-, leucine-, histidine-
8) In Table 8.1, what will be the result of conjugation between cultures 1 and 2 (reminder: F+
has a different meaning than Hfr)?
A) 1 will remain the same;
2 will become F+, leucine-, histidine-
B) 1 will become F-, leu+, his+;
2 will become F+, leu-, his-
C) 1 will become F-, leu-, his-;
2 will remain the same
D) 1 will remain the same;
2 will become F+, leu+, his+
E) 1 will remain the same;
2 will become F+ and recombina - ANS1 will remain the same; 2 will become F+, leucine-,
histidine-
In Table 8.1, if culture 1 mutates to Hfr, what will be the result of conjugation between the two
cultures?
A) They will both remain the same.
B) 1 will become F+, leu+, his+;
2 will become F+, leu+, his+
C) 1 will remain the same;
recombination will occur in 2
D) 1 will become F-, leu+, his+;
2 will become Hfr, leu+, his+
E) The answer cannot be determined based on the information provided. - ANS1 will remain the
same; recombination will occur in 2
Which of the following statements regarding a bacterium that is R+ is FALSE?
A) It possesses a plasmid.
B) R+ can be transferred to a cell of the same species.
C) It is resistant to certain drugs and heavy metals.
D) It is F+.
