MCB 3020 MICROBIOLOGY EXAM 4 QUESTIONS AND
ANSWERS
The process of importing free DNA into cells is known as __________.
a. tranposition
b. conjugation
c. specialized transduction
d. generalized transduction
e. transformation - Answers - transformation
Which of the following bacteria requires artificial assistance to become competent to
take up DNA?
a. Bacillus
b. E. coli
c. Haemophilus
d. Neisseria
e. Streptococcus - Answers - E. coli
A special sigma factor, __________, is used to transcribe genes encoding the
translocasome necessary for cell competency.
a. SigH
b. Sig70
c. SigT
d. SigC
e. Sig20 - Answers - SigH
__________ plasmids usually contain an oriT-like DNA replication origin that is
recognized by the conjugation apparatus of the transferable plasmid.
a. Mobilizable
b. Fertility
c. Hfr
d. F'
e. Conjugative - Answers - Mobilizable
During conjugation the DNA passes through the __________, NOT the __________.
a. membranes; pilus
b. pilus; membranes
c. pilus; phage
d. phage; pilus
e. F factor; phage - Answers - membranes; pilus
,The transfer of F factor in E. coli from one donor cell to a __________ cell results in two
__________ cells.
a. donor; donor
b. recipient; recipient
c. donor; recipient
d. recipient; donor
e. recipient; Hfr - Answers - recipient; donor
F factor contains how many origins of replication?
a. one
b. two
c. three
d. four
e. none - Answers - two
The 5'-end of the nicked strand of F factor moves through a pore in the conjugation
complex by a process driven by __________, which synthesizes a replacement strand
in the donor cell using the intact strand as template.
a. DNA pol I
b. DNA pol II
c. DNA pol III
d. ligase
e. Hfr - Answers - DNA pol III
Because the F plasmid can exist in extrachromosomal and integrated forms, it is
sometimes called a/an __________.
a. episome
b. F'
c. Hfr
d. lysogen
e. tranducing phage - Answers - episome
Approximately how long does it take for an Hfr strain to transfer its entire chromosome?
a. 30 minutes
b. 60 minutes
c. 100 minutes
d. 180 minutes
e. 300 minutes - Answers - 100 minutes
The recipient of Hfr conjugation __________ becomes an F+ or Hfr cell.
a. rarely
b. usually
c. always
d. never
e. frequently - Answers - rarely
, Interrupted mating involves breaking __________ bridges using a blender.
a. transformation
b. transduction
c. conjugation
d. transposition
e. bacteriophage - Answers - conjugation
A derivative F plasmid that contains host DNA is called an:
a. F plasmid
b. F+ plasmid
c. F- plasmid
d. F' plasmid
e. Hfr plasmid - Answers - F' plasmid
Some conjugation systems use __________ to stimulate transfer of genetic information.
a. transformation
b. pheromones
c. transduction
d. transposition
e. reversion - Answers - pheromones
Salmonella can conduct interspecies __________ with E. coli.
a. transduction
b. transformation
c. transposition
d. conjugation
e. recombination - Answers - conjugation
The process in which bacteriophages carry host DNA from one cell to another is known
as __________.
a. conjugation
b. transformation
c. transposition
d. recombination
e. transduction - Answers - transduction
In __________ the number of genes transferred is limited by the size of the phage
head.
a. transformation
b. conjugation
c. general recombination
d. specialized transduction
e. transposition - Answers - specialized transduction
Genes other than gal or bio can also be moved by __________ if lambda is used to
infect mutant host strains lacking the normal att site.
ANSWERS
The process of importing free DNA into cells is known as __________.
a. tranposition
b. conjugation
c. specialized transduction
d. generalized transduction
e. transformation - Answers - transformation
Which of the following bacteria requires artificial assistance to become competent to
take up DNA?
a. Bacillus
b. E. coli
c. Haemophilus
d. Neisseria
e. Streptococcus - Answers - E. coli
A special sigma factor, __________, is used to transcribe genes encoding the
translocasome necessary for cell competency.
a. SigH
b. Sig70
c. SigT
d. SigC
e. Sig20 - Answers - SigH
__________ plasmids usually contain an oriT-like DNA replication origin that is
recognized by the conjugation apparatus of the transferable plasmid.
a. Mobilizable
b. Fertility
c. Hfr
d. F'
e. Conjugative - Answers - Mobilizable
During conjugation the DNA passes through the __________, NOT the __________.
a. membranes; pilus
b. pilus; membranes
c. pilus; phage
d. phage; pilus
e. F factor; phage - Answers - membranes; pilus
,The transfer of F factor in E. coli from one donor cell to a __________ cell results in two
__________ cells.
a. donor; donor
b. recipient; recipient
c. donor; recipient
d. recipient; donor
e. recipient; Hfr - Answers - recipient; donor
F factor contains how many origins of replication?
a. one
b. two
c. three
d. four
e. none - Answers - two
The 5'-end of the nicked strand of F factor moves through a pore in the conjugation
complex by a process driven by __________, which synthesizes a replacement strand
in the donor cell using the intact strand as template.
a. DNA pol I
b. DNA pol II
c. DNA pol III
d. ligase
e. Hfr - Answers - DNA pol III
Because the F plasmid can exist in extrachromosomal and integrated forms, it is
sometimes called a/an __________.
a. episome
b. F'
c. Hfr
d. lysogen
e. tranducing phage - Answers - episome
Approximately how long does it take for an Hfr strain to transfer its entire chromosome?
a. 30 minutes
b. 60 minutes
c. 100 minutes
d. 180 minutes
e. 300 minutes - Answers - 100 minutes
The recipient of Hfr conjugation __________ becomes an F+ or Hfr cell.
a. rarely
b. usually
c. always
d. never
e. frequently - Answers - rarely
, Interrupted mating involves breaking __________ bridges using a blender.
a. transformation
b. transduction
c. conjugation
d. transposition
e. bacteriophage - Answers - conjugation
A derivative F plasmid that contains host DNA is called an:
a. F plasmid
b. F+ plasmid
c. F- plasmid
d. F' plasmid
e. Hfr plasmid - Answers - F' plasmid
Some conjugation systems use __________ to stimulate transfer of genetic information.
a. transformation
b. pheromones
c. transduction
d. transposition
e. reversion - Answers - pheromones
Salmonella can conduct interspecies __________ with E. coli.
a. transduction
b. transformation
c. transposition
d. conjugation
e. recombination - Answers - conjugation
The process in which bacteriophages carry host DNA from one cell to another is known
as __________.
a. conjugation
b. transformation
c. transposition
d. recombination
e. transduction - Answers - transduction
In __________ the number of genes transferred is limited by the size of the phage
head.
a. transformation
b. conjugation
c. general recombination
d. specialized transduction
e. transposition - Answers - specialized transduction
Genes other than gal or bio can also be moved by __________ if lambda is used to
infect mutant host strains lacking the normal att site.
