WGU 785 Final Exam

WGU 785 Final Exam Hemophilia Pedigree - Father has hemophilia, mother does not. What is the outcome for their kids? – His daughters would be carriers. This is x-link recessive. Autosomal: Dominant: - Autosomal: males and females equally affected. Dominant: non-carrier parents polymerase chain reaction (PCR) – The process of copying DNA in the lab. Uses Template DNA, Nucleotides (dNTPS), DNA Polymerase, and DNA primers. 3 Steps of PCR – 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) – 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 polymeraseputs the right one back in while DNA ligase seals it. Mismatch repair (MMR) occurs during: - 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? – Downloaded by charity nimo () lOMoARcPSD| 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? – 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? – DNA polymerase Nonsense Mutation – Change in 1 nucleotide produces a STOP codon Stop= nonsense because it is no more. Silent Mutation – Change in 1 nucleotide but codes for the same amino acid. Silent= the change doesn't change the name of the protein Missense Mutation – Change in 1 nucleotide leads to a code for a different amino acid. Missense = mistake was made. What happends during RNA splicing? – During RNA splicing introns are cut out, the remaining exons are joined together. 5'ATG AGT CTC TCT 3' Find the DNA template strand. – 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? – 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. Downloaded by charity nimo () lOMoARcPSD| How would a mutation from CTC to ATC affect the protein sequence? (CTC/ATC - coding strand, AUC - mRNA strand) – This will make a missense mutation because it changes the name of the protein. (look at the chart provided.) missense = mistake DNA replication process – DNA ->Transcription -> RNA -> Translation -> Polypeptide Describe how you would find what ionized Alanine looks like. – 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. – 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. – 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.