WGU C785 EVALUATION SCRIPT
GRADED A+ SOLVED SOLUTIONS
◉ A patient has received a large dose of ionizing radiation at his
place of employment. Which scenario is accurate?
Ligase removes a single damaged base and replaces it with a new
nucleotide.
Double-stranded DNA breaks are being repaired by
nonhomologous end joining, without the use of a homologous
template.
The homologous recombination pathway is upregulated and is
facilitating the removal of mismatched bases.
A string of damaged nucleotides is removed and replaced by a
new nucleotide sequence in the base excision repair pathway.
Answer: Double-stranded DNA breaks are being repaired by
nonhomologous end joining, without the use of a homologous
template.
Due to the large dose of ionizing radiation, the patient has many
double-stranded DNA breaks, and undamaged homologous DNA is
in short supply. Nonhomologous end-joining will be used to fix
these double-strand breaks.
,◉ Immediately following transcription, mRNA must be processed
before it is transported to the cytoplasm to undergo translation.
Which statement correctly describes mRNA processing?
Alternative combinations of introns can be linked together to
produce closely related gene products.
Exons are removed and introns are inserted into the mature
mRNA sequence.
mRNA is folded into beta-pleated sheets and alpha helices to
produce a mature mRNA sequence.
Introns are spliced out and exons are connected to produce a
mature mRNA sequence.
Answer: Introns are spliced out and exons are connected to
produce a mature mRNA sequence.
Introns are removed from the mRNA sequence and the remaining
exons are spliced together to create the mature mRNA.
◉ A point mutation has altered the amino acid sequence of a
neuronal tau protein, causing serine (Ser) at position 202 to be
mutated to proline (Pro). Which set of codons below corresponds
to this mutation?
,TCT to CCT
AGA to GGA
CGA to AGG
AGG to CCC
Answer: TCT to CCT
TCT is a codon for Ser, and CCT is a codon for Pro. TCT to CCT is a
point mutation that changes Ser to Pro.
◉ Which of the following is required for DNA polymerase to
replicate template DNA in PCR?
RNA primers
tRNA
RNA polymerase
DNA primers
Answer: DNA Primers
, DNA primers are used in the PCR process.
◉ A portion of the HLA gene and its associated amino acid
sequence are shown below. If cytosine is deleted from codon 101,
what will be the resulting amino acid sequence?
Ser Tyr Glu
Glu Met Leu
Glu Pro Cys
Glu His Ala Asp
Answer: Glu Met Leu
Deletion of cytosine (C) from codon 101 leads to the DNA
sequence 5'-GAG ATG CTG AT-3', which corresponds to the amino
acid sequence Glu Met Leu.
◉ Inheriting mutations in the BRCA-1 or BRCA-2 gene can
increase an individual's likelihood of developing breast cancer or
ovarian cancer. How can PCR be used to assess an individual's
susceptibility to developing these cancers?
GRADED A+ SOLVED SOLUTIONS
◉ A patient has received a large dose of ionizing radiation at his
place of employment. Which scenario is accurate?
Ligase removes a single damaged base and replaces it with a new
nucleotide.
Double-stranded DNA breaks are being repaired by
nonhomologous end joining, without the use of a homologous
template.
The homologous recombination pathway is upregulated and is
facilitating the removal of mismatched bases.
A string of damaged nucleotides is removed and replaced by a
new nucleotide sequence in the base excision repair pathway.
Answer: Double-stranded DNA breaks are being repaired by
nonhomologous end joining, without the use of a homologous
template.
Due to the large dose of ionizing radiation, the patient has many
double-stranded DNA breaks, and undamaged homologous DNA is
in short supply. Nonhomologous end-joining will be used to fix
these double-strand breaks.
,◉ Immediately following transcription, mRNA must be processed
before it is transported to the cytoplasm to undergo translation.
Which statement correctly describes mRNA processing?
Alternative combinations of introns can be linked together to
produce closely related gene products.
Exons are removed and introns are inserted into the mature
mRNA sequence.
mRNA is folded into beta-pleated sheets and alpha helices to
produce a mature mRNA sequence.
Introns are spliced out and exons are connected to produce a
mature mRNA sequence.
Answer: Introns are spliced out and exons are connected to
produce a mature mRNA sequence.
Introns are removed from the mRNA sequence and the remaining
exons are spliced together to create the mature mRNA.
◉ A point mutation has altered the amino acid sequence of a
neuronal tau protein, causing serine (Ser) at position 202 to be
mutated to proline (Pro). Which set of codons below corresponds
to this mutation?
,TCT to CCT
AGA to GGA
CGA to AGG
AGG to CCC
Answer: TCT to CCT
TCT is a codon for Ser, and CCT is a codon for Pro. TCT to CCT is a
point mutation that changes Ser to Pro.
◉ Which of the following is required for DNA polymerase to
replicate template DNA in PCR?
RNA primers
tRNA
RNA polymerase
DNA primers
Answer: DNA Primers
, DNA primers are used in the PCR process.
◉ A portion of the HLA gene and its associated amino acid
sequence are shown below. If cytosine is deleted from codon 101,
what will be the resulting amino acid sequence?
Ser Tyr Glu
Glu Met Leu
Glu Pro Cys
Glu His Ala Asp
Answer: Glu Met Leu
Deletion of cytosine (C) from codon 101 leads to the DNA
sequence 5'-GAG ATG CTG AT-3', which corresponds to the amino
acid sequence Glu Met Leu.
◉ Inheriting mutations in the BRCA-1 or BRCA-2 gene can
increase an individual's likelihood of developing breast cancer or
ovarian cancer. How can PCR be used to assess an individual's
susceptibility to developing these cancers?
