Biochemistry C785 Module 1 (Answered) 2022/2023

Biochemistry C785 Module 1 (Answered) 2022/2023 What is translation? Process by which mRNA is decoded and a protein is produced polymerase chain reaction (PCR) A method of producing thousands of copies of DNA segment using the enzyme DNA polymerase DNA primers in PCR are needed to? a initiate synthesis of the new DNA molecule dNTPs are the building blocks of DNA DNA polymerase III adds bases to the new DNA chain; proofreading the chain for mistakes Excision Repair locates and repairs incorrect sequence by removing a segment of the DNA and then adding the correct nucleotides Base Excision Repair (BER) is what DNA repair that first excises modified bases and then replaces the entire nucleotide mismatch repair does what repair enzymes correct errors in base pairing homologous recombination repairs what kind of breaks double strand breaks Nucleotide Excision Repair (NER) is what kind of repair used to repair deletions, insertions and helix-distorting lesions, thymine dimers complete dominance a relationship in which one allele is completely dominant over another incomplete dominance Situation in which one allele is not completely dominant over another allele Codominance A condition in which neither of two alleles of a gene is dominant or recessive. franeshift mutation a single base is added or deleted from DNA What is a nonsense mutation? A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein. What is a silent mutation? alters a base but does not change the amino acid missense mutation A base-pair substitution that results in a codon that codes for a different amino acid. Epigenetics the study of environmental influences on gene expression that occur without a DNA change Epigenetic repression carried out by DNA and nucleosome modifications that result in increased nucleosome packing that makes the DNA less available for transcription. decreased gene expression epigenetic repression where the methylation present is packed tightly Epigenetic activation nucleosome and DNA modifications that result in the loosening of the chromatin structure to allow for transcription to take place. Increased gene expression Usually achieved by other chemical tags that loosen up DNA coiling so transcription can occur. RNA primer short piece of RNA needed for DNA polymerase to start Introns are removed from the mRNA after transcription of the gene occurs Steps of Insulin Production 1. Transcription factors bind to the promoter. 2. Transcription factors recruit RNA polymerase. 3. RNA polymerase makes insulin mRNA. 4. Insulin mRNA is used to make insulin protein. Genotype genetic makeup Phenotype An organism's physical appearance, or visible traits. When given the coding (non-template) DNA 5' CGG TAT TGC 3' what is the non-coding (template) complementary to DNA? 1. You want the non-coding template 2. Change to 3' to 5' 3. Write from 3 (opposite direction) 4. Change G to C, C to 5. Change A to T, T to A 3' GCC ATA ACG 5' Results when there is an insertion or deletion of one or more base pairs (if the number of base pairs is not a multiple of three) Frameshift If a point mutation results in a shorter protein product because a stop codon is introduced, it is called a _____________________ mutation. Nonsense If DNA contains a point mutation, transcription will result in the production of __________________ with the incorrect sequence. mRNA If there is a missense mutation, during the process of translation, the wrong _____________ ________________ will be inserted into the growing polypeptide chain. amino acid "3 nucleotide codon" patterns gets out of sync because of an insertion / deletion