Questão 1
Questão
Select the statements that apply to prokaryotic DNA
Responda
-
Thy have a single, circular chromosome
-
There is a single point of origin for DNA replication
-
DNA replication is bidirectional
-
They have lots of linear DNA
-
There are multiple points of origin
Questão 2
Questão
Select the statements that apply to eukaryotic DNA
Responda
-
They have lots of linear DNA
-
There are multiple points of origin for DNA replication
-
DNA replication is bidirectional
-
There is one, circular chromosome
-
There is one point of origin for DNA replication
Questão 3
Questão
What is the role of the primase enzyme in DNA replication
Responda
-
It adds RNA primers to the template strand
-
It unzips the DNA strand
-
It releases the tension at the DNA fork
-
It join synthesised fragments with phosphodiester bonds
Questão 4
Questão
What is the role of the DNA Polymerase III enzyme in DNA replication
Responda
-
It adds complimentary nucleotides from the reactive 3' hydroxyl group left by the RNA primer
-
It adds complimentary base pairs from the reactive 3' phosphate group left by the RNA primer
-
It binds at the 5' end and synthesises the new strand by adding base pairs
-
It binds at the 3' end and synthesises the new strand by adding phosphodiester bonds
Questão 5
Questão
What is the role of the Helicase enzyme in DNA replication
Responda
-
It unwinds the DNA from the AT rich point of origin
-
It unwinds the DNA from the point of origin
-
It unwinds the DNA from the CG rich point of origin
-
It puts the DNA back together after synthesis
Questão 6
Questão
What is the role of the Topoisomerase enzyme in DNA replication
Responda
-
It releases the tension at the replication fork by making cuts and then 'glues' them back together
-
It binds to the DNA to stop the leading and lagging strand fro getting back together
-
It unzips the gene
-
It checks the newly added bases against the template to make sure they are correct
Questão 7
Questão
What is the role of single stranded binding proteins in DNA replication
Responda
-
They protect the single strands from degradation
-
They prevent the single strands from coming back together again
-
They make RNA primers
-
The release the tension at the replication fork by making cuts and then gluing them back together again
Questão 8
Questão
What is the role of Ligase in DNA replication
Questão 9
Questão
The overall direction of DNA synthesis on the lagging strand is in the 3'-5' direction
Questão 10
Questão
How are errors in DNA sequence corrected during replication?
Responda
-
With exonuclease activity of DNA Polymerase III
-
With endonuclease activity of DNA polymerase III
-
With exonuclease activity of DNA Polymerase II
-
With endonuclease activity of DNA polymerase II
Questão 11
Questão
[blank_start]During[blank_end] DNA replication, errors in DNA sequence are corrected with [blank_start]exonuclease[blank_end] activity of DNA polymerase [blank_start]III[blank_end]. It checks the newly added bases against the [blank_start]template[blank_end], removes it and replaces it so synthesis can continue as normal.
Responda
-
exonuclease
-
endonuclease
-
III
-
II
-
template
-
lagging strand
-
During
-
After
Questão 12
Questão
[blank_start]After[blank_end] DNA replication, any errors in the sequence are corrected by [blank_start]endonuclease[blank_end] activity of DNA polymerase [blank_start]II[blank_end]. it removes the incorrect bases and some either side, [blank_start]DNA polymerase[blank_end] corrects the mistake, then [blank_start]Ligase[blank_end] [blank_start]joins[blank_end] the newly synthesised sequence to the pre-existing sequence with [blank_start]phosphodiester bonds[blank_end].
Responda
-
After
-
During
-
endonuclease
-
exonuclease
-
I
-
III
-
DNA polymerase
-
Ligase
-
joins
-
detaches
-
phosphodiester bonds
-
hydrogen bonds
Questão 13
Questão
Failure to [blank_start]correct[blank_end] mistakes in DNA sequence will lead to [blank_start]permanent[blank_end] changes in [blank_start]DNA[blank_end] sequence, in turn leading to a [blank_start]mutation[blank_end]
Responda
-
correct
-
permanent
-
DNA
-
mutation
Questão 14
Questão
PCR (P[blank_start]olymerase[blank_end] C[blank_start]hain[blank_end] R[blank_start]eaction[blank_end]) [blank_start]amplifies[blank_end] a gene so you can have [blank_start]multiple[blank_end] copies of the [blank_start]same[blank_end] gene. There are no [blank_start]lagging[blank_end] strands (unlike prokaryotic replication) as both strands are synthesised [blank_start]continuously[blank_end].
Responda
-
olymerase
-
hain
-
eaction
-
amplifies
-
multiple
-
same
-
lagging
-
continuously
Questão 15
Questão
Select the key components of PCR
Questão 16
Questão
At what temperature does Denaturation of double stranded DNA occur during PCR?
Questão 17
Questão
At what temperature does Annealing of DNA templates occur during PCR?
Questão 18
Questão
At what temperature does extension/elongation occur during PCR?
Questão 19
Questão
What is the role of DNA polymerase I during DNA replication
Responda
-
It removes the RNA primers on Okazaki fragments
-
It fills in the gaps left by removed RNA primers with complimentary nucleotides
-
It adds the RNA primers on Okazaki fragments
-
It fills in the gaps left by removed DNA primers with RNA
Questão 20
Questão
DNA replication begins with [blank_start]Helicase[blank_end] unwinding the DNA strands from an [blank_start]AT[blank_end] rich origin of replication, with [blank_start]Single[blank_end] [blank_start]Stranded[blank_end] [blank_start]Binding[blank_end] [blank_start]Proteins[blank_end] (SSBP) protecting the strands from [blank_start]degradation[blank_end] and stopping them from coming back together again. Topoisomerase releases [blank_start]tension[blank_end] at the replication fork by cutting and gluing the strands back together again. [blank_start]Primase[blank_end] adds an [blank_start]RNA[blank_end] primer with a chemically reactive [blank_start]3[blank_end]’ hydroxyl group, then DNA Polymerase [blank_start]III[blank_end] adds complimentary [blank_start]nucleotides[blank_end] from that hydroxyl group. On the leading strand, synthesis happens [blank_start]continuously[blank_end] in the [blank_start]5'-3'[blank_end] direction, however on the lagging strand this occurs [blank_start]discontinuously[blank_end] in the overall [blank_start]3'-5'[blank_end] direction in [blank_start]Okazaki[blank_end] fragments. RNA primers are added intermittently along the strand, with DNA Polymerase III adding the complementary nucleotides in the 5’-3’ direction. DNA Polymerase [blank_start]I[blank_end] then comes and removes the RNA primers on the leading and lagging strands, and fills in the gaps with [blank_start]complimentary[blank_end] nucleotides. [blank_start]Ligase[blank_end] forms the bonds between 3’ hydroxyl and 5’ phosphate groups, completing DNA synthesis.
Responda
-
Helicase
-
AT
-
Single
-
Stranded
-
Binding
-
Proteins
-
degradation
-
tension
-
Primase
-
RNA
-
3
-
III
-
nucleotides
-
continuously
-
5'-3'
-
discontinuously
-
3'-5'
-
Okazaki
-
I
-
complimentary
-
Ligase