exam 3 Flashcards
It is movement of the Holliday junction up and down the DNA by breaking and reforming the hydrogen bonds between the bases
a) Sinapse
b) Branch migration
c) Isomerisation
B
_____________ force the ssDNA into the helical conformation
a) RecA
b) SSB
c) RecBCD
d) RecQ
e) a and b
A
what are class 2 transposons
move directly from one place to another within the genome using cut and paste rather than copy and paste using transposase
The transposase cut and paste the transposon
a) True
b) False
true
In the single strand invasion model of genetic recombination one strand of the DNA molecules is cut and invade the other double strand DNA molecule until it finds its complementary sequence
a) True
False
True
____________________ recombinant molecules are generated when each molecule contains a region of heteroduplex DNA that spans the region of branch migration (configuration II)
a) holliday double strand invasion model
b) holliday single strand invasion model
c) Double break repair model
A
The transposons are also name as
a) jumping genes
b) mobile genetic elements
c) junk DNA
d) a and b
e) a, b and c
E
Transposon with inactive transposase continue to jump through the genome
a) True
b) False
true
A common way of delivering transposons is to use ______________ that cannot replicate in the recipient cells. pGP704 is an AmpR plasmid that is unable to replicate unless the Pi protein (encoded by the pir gene) is provided in the recipient cell.
a) Plasmid
b) Phage
Suicide Vector
Suicide Vector
______________ is required for recombination (prepare the single strand end of DNA to invade the other double-strand DNA – first step in recombination), degradation of foreign linear DNA and in restart the replication when the replication fork stalls at single or double-strand-breaks in the template DNA.
a) RecA
b) SSB
c) RecBCD
d) RecQ
C
Which proteins are involved in mismatch repair?
a) MutS
b) MutH
c) MutL
d) all of the above
D
RecBCD is required for
a) Recombination
b) Degradation of foreign linear DNA
c) Restart replication
d) a, b and c
D
In the Out-site end Transposition, each IS element can transpose independently as long as the transposase acts on both of its ends
a) True
False
true
________________ is the cut and ligation of DNA strand in the Holliday junction
a) Synapse
b) Branch migration
c) Isomerisation
d) Resolution
D
In both transposition mechanism the cut 5’ ends of the target DNA are join to the free 3’ end of the transposon and the target DNA 3’ end is used as a primer for replication until the free 5’ end is reached
A) true
B) false
true
Mention the properties of the transposable elements
a) Movement is not totally random, not capable of self-replication, Transposition mediated by site-specific recombination and Transposition can be accompanied by duplication
b) Movement is not totally random, not capable of self-replication, Transposition mediated by site-specific recombination
c) Movement is not totally random, it is capable of self-replication, Transposition mediated by site-specific recombination and Transposition can be accompanied by duplication
B
DnaK binds to sigma-32 and makes sigma-32 more susceptible to protease degradation.
a) True
False
true
Pathway used to prepare single stranded DNA for D-loop formation in E. coli
a) RecBCD pathway
b) RecF pathway
c) RecE pathway
B
In base excision repair, the lesion is removed by \_\_\_\_\_\_\_\_\_\_ a) DNA glycosylase b) Excisionase c) Transposase d) DNA polymerase Integrase
A
The enzyme of Escherichia coli is a nuclease that initiates the repair of double-stranded DNA breaks by homologous recombination.
a) RNA polymerase
b) DNA polymerase
c) DNA ligase
d) RecBCD
e) DNA glycolase
D
The definitive experiment proving non replicative transposition in vivo for transposon Tn10 was done by Bender and Kleckner
a) True
False
True
______________ is formed when two DNA molecules are joined through the formation of the D-loop
a) Synapse
b) Branch migration
c) Isomerisation
d) Resolution
synapse
Resolvase promotes recombination
a) True
False
true
Typically, the transposition frequency is decrease when a transposon enters a naive host or immediately after DNA replication
a) True
False
False,
Increase
\_\_\_\_\_\_\_\_\_\_\_\_\_\_ is formed when two DNA molecules are joined through the formation of the D-loop a) Synapse b) Branch migration c) Isomerisation Resolution
A
The major pathway of recombination in E.coli is
a) RecBCD pathway
b) RecF pathway
c) RecE pathway
A
The rearrangement between the strands after the formation of the Holliday junction called
a) Synapse
b) Branch migration
c) Isomerisation
d) Resolution
C
______________ is required for recombination (prepare the single strand end of DNA to invade the other double-strand DNA – first step in recombination), degradation of foreign linear DNA and in restart the replication when the replication fork stalls at single or double-strand-breaks in the template DNA.
a) RecA
b) SSB
c) RecBCD
d) RecQ
e) RecE
C