WorksheetsMCB103 Module 2
Total questions: 45
Worksheet time: 46mins
Refers to DNA segment damage caused by, base alteration, base deletion, sugar alteration, and strand break.
(a)
Classification of repairable lesions
A class of repairable lesion that may be caused by physical or chemical mutagens.
(a)
Two nucleotides of a DNA form a covalent in between them (from the same strand)
(a)
Two nucleotides of a DNA form a covalent in between them (from opposite strands)
(a)
This type of cross links is highly toxic due to it inhibiting the separation of DNA strand. Thus, compromising the replication and transcription process.
Intrastrand cross links
Interstrand cross links
Repair System
DNA glycosylase, AP endnonuclease, DNA polymerase I, DNA ligase
(a)
Repair System
Uvr-A, Uvr-B, Uvr-C, DNA pol. 1, DNA ligase
(a)
Repair System
Dam methylase, MutS, MutL, MutH, Exonuclease, DNA helicase II, SSB protein, DNA pol. III, DNA ligase
(a)
Repair System
Photolyase (photoreactivation enzyme)
(a)
Repair System
RecBCD, RecA, DNA pol. I, RuvABC, Ligase
(a)
Repair System
Ku complex, Ligase, DNA pol. I, XRCC4
(a)
Repair System
RecA, LexA, UmuCD
(a)
Base Excision Repair (BER) involves a category of enzymes called (a) .
In BER, these enzymes can recognize an abnormal base and cleave the bond between it and the sugar in the DNA.
(a)
Assuming the base removed in (1) is a purine, what us this region called?
(a)
Assuming the base removed in (1) is a pyrimidine, what us this region called?
(a)
2
(a)
3
(a)
This type of system can repair many types of DNA damage including Thymine dimers and chemically modified bases; Missing bases, some types of cross-links.
(a)
In E. coli, the NER system requires four key proteins: ___, ___, ___, and ___ named so as they are involved in Ultraviolet light repair of pyrimidine dimers
(a)
In NER these enzymes finish the repair job
(a)
In NER, the (a) complex tracks along the DNA in search of a damaged DNA.
In NER, after the damage is detected, ___ is released and ___ binds and cuts both sides of the thymine dimer.
(a)
In NER, (a) is a helicase that removes the damaged region.
In photoreactivation repair this enzyme repairs damage caused by UV light.
(a)
Photolyase only works under visible light. The red to violet spectrum.
True
False
If proofreading fails, the (a) comes to the rescue.
NER and MDMR are found in both eukaryotes and prokaryotes.
True
False
Mismatch repair enzymes in E. coli.
(a)
In mismatch repair, this enzyme it can distinguish between the parental strand and the daughter strand.
(a)
Mismatch repair. Immediately after replication, the parental strand is methylated whereas the daughter is not yet! This DNA strand is known as.
(a)
an enzyme that adds a methyl group to the adenine of the sequence 5’-GATC-3’
(a)
In MDMR, this enzyme is the linker.
(a)
(a) protein is activated by single stranded DNA which is induced through strong DNA damages.
(a) is a repressor protein that binds sequences in promoters of SOS-regulated genes and prevents expression under non-stress conditions.
A signal generated upon DNA damage relieves repression by LexA by resulting in (a)
Signal for DNA damage is a nucleoprotein filament composed of ___ and ___.
(a)
Replication of DNA past a lesion in the template strand: (a) .
TLS performed by ___ (not by replicative DNA polymerase - Pol III). Whose Catalytic unit of DNA Pol V is ___.
(a)
Mutations due to TLS are referred to as (a) .
___, ___, and ____ are all required for TLS.
(a)
E. coli umuCD mutants are “ (a) ” after UV treatment.
Number of breaks that occur each day in a typical human cell.
(a)
DNA breaks may be repaired by ___ and ___ .
(a)
