WGU 785 Final Exam
Hemophilia Pedigree - Father has hemophilia, mother does not. What is the outcome for their kids?
ans :His daughters would be carriers. This is x-link recessive.
Autosomal:
Dominant: ans :Autosomal: males and females equally affected.
Dominant: non-carrier parents
polymerase chain reaction (PCR) ans :The process of copying DNA in the lab. Uses Template DNA,
Nucleotides (dNTPS), DNA Polymerase, and DNA primers.
3 Steps of PCR ans :1. Denaturation: DNA is heated to 95C to separate it.
2. Annealing: reaction is cooled to 50C; primers stick to the DNA you want to copy and add DNA
polymerase.
3. Elongation: reaction heated to 70C and DNA polymerase, adding nucleotides building a new DNA
strand.
Base Excision Repair (BER) ans :How you repair a mutation. BER is used to repair damage to a base
caused by harmful molecules. You remove the base that is damaged and replace it. *BER removes a
single nucleotide*
DNA glycolsylase - sees damaged DNA and removes it.
DNA polymerase-puts the right one back in while DNA ligase seals it.
Mismatch repair (MMR) occurs during: ans :replication. DNA polymerase proofreads but sometimes a
mismatch pair gets through. MMR removes a large section of the nucleotides from the new DNA and
DNA polymerase tries again. (Ex: C-T instead of C-A)
Mismatch Repair corrects what kind of DNA damage? ans :When a base is mismatched due to errors in
replication. Such as G-T instead of G-C. DNA polymerase comes by and fixes it.
What happens when DNA polymerase binds to DNA to make RNA? ans :TRANSCRIPTION! DNA
polymerase takes the individual nucleotides and matches them to the parental sequences to ensure a
correct pair. It must bind with RNA primer to work.
What is needed for DNA replication? ans :DNA polymerase
Nonsense Mutation ans :Change in 1 nucleotide produces a STOP codon Stop= nonsense because it is no
more.
Silent Mutation ans :Change in 1 nucleotide but codes for the same amino acid. Silent= the change
doesn't change the name of the protein
Missense Mutation ans :Change in 1 nucleotide leads to a code for a different amino acid. Missense =
mistake was made.
What happends during RNA splicing? ans :During RNA splicing introns are cut out, the remaining exons
are joined together.
5'ATG AGT CTC TCT 3'
Find the DNA template strand. ans :3'TAC TCA GAG AGA 5'
The DNA template strand is complimentary. So start with the opposite number, then go L-R with the
complimentary letter.
5'ATG AGT CTC TCT 3'
What is the corresonding mRNA sequence? ans :5'AUG AGU CUC UCU 3'
, This sequence is the same as the coding strand except T changes to U because it is RNA. RNA doesn't
have T.
How would a mutation from CTC to ATC affect the protein sequence? (CTC/ATC - coding strand, AUC -
mRNA strand) ans :This will make a missense mutation because it changes the name of the protein. (look
at the chart provided.) missense = mistake
DNA replication process ans :DNA ->Transcription -> RNA -> Translation -> Polypeptide
Describe how you would find what ionized Alanine looks like. ans :This is an amino acid. Look for the "R"
group. Alanine is a hydrophobic amino acid that has CH3. It is a weak interaction. An ionized acid will
have a + or - charge.
Describe what causes the misfolding of protein in Alzheimer's Disease. ans :Protein misfolding is caused
by intracellular tangles and extracellular plaques (senile plaques) caused by abnormal protein
aggregation.
TAU is fibrous material inside cells where the connections are lost. This becomes defective and forms
filaments in the neuron.
Amyloid-Beta is a large precursor protein in the cell. Excess amyloid-beta creates senile plaques. This
starts in the hippocampus and moves up.
Describe the process of neurodegenerative protein aggregation. ans :Alzheimer's is the most common
neurodegenerative disease. The formation of aggregated amyloid-beta fibers is another characterisitc of
Alzheimer's. However, neurodegeneration and memory loss can be detected before amyloid fibers
accumulate in the brain.
What are the molecules that help denatured proteins with folding? ans :Molecular chaperones are
protein helpers. They bind to the newly made polypeptide and enable proper folding. Proper protein
folding is vital b/c proteins that do not fold properly can lead to a variety of diseases. Normally, the
chaperones that help new proteins fold can also help misfolded proteins refold into the correct
structure.
Genetic mutations that substitute one amino acid for another can cause incorrect folding.
What are the 4 levels of protein structure? ans :1. Primary-chain of amino acids. PEPTIDE bonds form a
polypeptide chain. This is a covalent bond (very strong) and does not denature.
2. Secondary-alpha helix and beta sheet. HYDROGEN bonds that contain the carboxyl group and amino
groups. Denatured by salt and pH change.
3. Tertiary-side chain interaction (R group). Changes are seen with high temp, salt, change in pH, and
reducing agents. (ex: sickle cell, arthritis, hemophilia)
4. Quarternary-more than 1 polypeptide. Change seen with increased temp. (Ex: Hgb)
Hydrogen bonds are formed from ans :2 polar amino acids.
(Contains Oxygen and nitrogen-OH, NH, NH2. On exterior surface)
What structure would be unaffected by complete denaturation of its multi-subunit? ans :PRIMARY.
Peptide bonds are strong and covalent. The primary structure is located at the backbone and does not
denature.
What is the simplest way to denature a protein? ans :Heat it up. The tertiary structure is hydrophobic.
The tertiary structure is a protein structure stabilized primarily by the hydrophobic effect.
What is the secondary structure made up of? ans :Alpha helixes and beta sheets
Hemophilia Pedigree - Father has hemophilia, mother does not. What is the outcome for their kids?
ans :His daughters would be carriers. This is x-link recessive.
Autosomal:
Dominant: ans :Autosomal: males and females equally affected.
Dominant: non-carrier parents
polymerase chain reaction (PCR) ans :The process of copying DNA in the lab. Uses Template DNA,
Nucleotides (dNTPS), DNA Polymerase, and DNA primers.
3 Steps of PCR ans :1. Denaturation: DNA is heated to 95C to separate it.
2. Annealing: reaction is cooled to 50C; primers stick to the DNA you want to copy and add DNA
polymerase.
3. Elongation: reaction heated to 70C and DNA polymerase, adding nucleotides building a new DNA
strand.
Base Excision Repair (BER) ans :How you repair a mutation. BER is used to repair damage to a base
caused by harmful molecules. You remove the base that is damaged and replace it. *BER removes a
single nucleotide*
DNA glycolsylase - sees damaged DNA and removes it.
DNA polymerase-puts the right one back in while DNA ligase seals it.
Mismatch repair (MMR) occurs during: ans :replication. DNA polymerase proofreads but sometimes a
mismatch pair gets through. MMR removes a large section of the nucleotides from the new DNA and
DNA polymerase tries again. (Ex: C-T instead of C-A)
Mismatch Repair corrects what kind of DNA damage? ans :When a base is mismatched due to errors in
replication. Such as G-T instead of G-C. DNA polymerase comes by and fixes it.
What happens when DNA polymerase binds to DNA to make RNA? ans :TRANSCRIPTION! DNA
polymerase takes the individual nucleotides and matches them to the parental sequences to ensure a
correct pair. It must bind with RNA primer to work.
What is needed for DNA replication? ans :DNA polymerase
Nonsense Mutation ans :Change in 1 nucleotide produces a STOP codon Stop= nonsense because it is no
more.
Silent Mutation ans :Change in 1 nucleotide but codes for the same amino acid. Silent= the change
doesn't change the name of the protein
Missense Mutation ans :Change in 1 nucleotide leads to a code for a different amino acid. Missense =
mistake was made.
What happends during RNA splicing? ans :During RNA splicing introns are cut out, the remaining exons
are joined together.
5'ATG AGT CTC TCT 3'
Find the DNA template strand. ans :3'TAC TCA GAG AGA 5'
The DNA template strand is complimentary. So start with the opposite number, then go L-R with the
complimentary letter.
5'ATG AGT CTC TCT 3'
What is the corresonding mRNA sequence? ans :5'AUG AGU CUC UCU 3'
, This sequence is the same as the coding strand except T changes to U because it is RNA. RNA doesn't
have T.
How would a mutation from CTC to ATC affect the protein sequence? (CTC/ATC - coding strand, AUC -
mRNA strand) ans :This will make a missense mutation because it changes the name of the protein. (look
at the chart provided.) missense = mistake
DNA replication process ans :DNA ->Transcription -> RNA -> Translation -> Polypeptide
Describe how you would find what ionized Alanine looks like. ans :This is an amino acid. Look for the "R"
group. Alanine is a hydrophobic amino acid that has CH3. It is a weak interaction. An ionized acid will
have a + or - charge.
Describe what causes the misfolding of protein in Alzheimer's Disease. ans :Protein misfolding is caused
by intracellular tangles and extracellular plaques (senile plaques) caused by abnormal protein
aggregation.
TAU is fibrous material inside cells where the connections are lost. This becomes defective and forms
filaments in the neuron.
Amyloid-Beta is a large precursor protein in the cell. Excess amyloid-beta creates senile plaques. This
starts in the hippocampus and moves up.
Describe the process of neurodegenerative protein aggregation. ans :Alzheimer's is the most common
neurodegenerative disease. The formation of aggregated amyloid-beta fibers is another characterisitc of
Alzheimer's. However, neurodegeneration and memory loss can be detected before amyloid fibers
accumulate in the brain.
What are the molecules that help denatured proteins with folding? ans :Molecular chaperones are
protein helpers. They bind to the newly made polypeptide and enable proper folding. Proper protein
folding is vital b/c proteins that do not fold properly can lead to a variety of diseases. Normally, the
chaperones that help new proteins fold can also help misfolded proteins refold into the correct
structure.
Genetic mutations that substitute one amino acid for another can cause incorrect folding.
What are the 4 levels of protein structure? ans :1. Primary-chain of amino acids. PEPTIDE bonds form a
polypeptide chain. This is a covalent bond (very strong) and does not denature.
2. Secondary-alpha helix and beta sheet. HYDROGEN bonds that contain the carboxyl group and amino
groups. Denatured by salt and pH change.
3. Tertiary-side chain interaction (R group). Changes are seen with high temp, salt, change in pH, and
reducing agents. (ex: sickle cell, arthritis, hemophilia)
4. Quarternary-more than 1 polypeptide. Change seen with increased temp. (Ex: Hgb)
Hydrogen bonds are formed from ans :2 polar amino acids.
(Contains Oxygen and nitrogen-OH, NH, NH2. On exterior surface)
What structure would be unaffected by complete denaturation of its multi-subunit? ans :PRIMARY.
Peptide bonds are strong and covalent. The primary structure is located at the backbone and does not
denature.
What is the simplest way to denature a protein? ans :Heat it up. The tertiary structure is hydrophobic.
The tertiary structure is a protein structure stabilized primarily by the hydrophobic effect.
What is the secondary structure made up of? ans :Alpha helixes and beta sheets
