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WGU BiochemistryTerms in this set (100)DNA replication is ___________, which allows each of the twostrands to serve as a _______ for the new strands. b. semiconservative, templateDNA replication is semiconservative, meaning that each new duplex has one original (parent)strand and one new strand. Because the two parent strands are separated during replication andthe base pairing is predictable, each parent strand can serve as a template for the new strandsynthesis.Which of the following enzymes does NOT assist the DNApolymerase on the lagging strand to overcome its twoproblems? (Recall that the DNA polymerase can only makeDNA in the 5'->3' direction, and it must bind a double-strandednucleotide polymer before it can start making its own DNApolymer.)c. HelicaseHelicase unwinds the double stranded DNA to allow for replication, but this is not a problem forthe DNA polymerase.Several components of cigarette smoke, includingbenzopyrene, insert themselves (intercalate) into the DNA andlead to several types of mutations such as frameshift mutations,including both insertions and deletion. Which of the followingrepair pathways would be used to repair this type of damage? c. Nucleotide Excision RepairNucleotide excision repair is used to repair deletions, insertions, and helix-distorting lesions, suchas thymine dimers.WGU Biochemistry
Maternal smoking during pregnancy is hazardous yet commonin many places. Many studies have associated prenatalsmoking to unhealthy physical and psychological outcomes forthe baby. Researchers know that maternal smoking affects areepigenetic in nature. Which of the following events can beconsidered epigenetic in nature? a. Changes in chromatin structureFrame shift mutations are a kind of mutations which result from addition of deletion of a nucleotidebase resulting in an altered reading frame and ultimately a different protein, than the one the geneoriginally encoded. Frameshift mutations are genetic changes because they alter the DNAsequence, whereas epigenetic changes do not alter the DNA sequence. Epigenetic changes aremodifications to genomic structure (not sequence) that are caused by the external environment.These environmental factors affect the overall chromatin structure to allow more or less "access" tothe DNA by gene expression machinery to turn the genes "on" or "off". In other words, epigeneticscan alter gene expression without changing the underlying DNA sequences. The changes may ormay not be heritable, depending on the location and circumstances.Blood type is an example of what type of inheritance? a. CodominanceThe genes that produce the A and B antigen proteins can both be expressed independently, and aheterozygote (someone with both genes) will be produce both A and B proteins - neither willdominate the other. The is an example of codominance.