BIOC 385 Exam 4 (with Complete Solutions)

An Ames test of a compound suspected to be a mutagen was examined before and after incubation with rat liver extract. Based on the results shown, what do you conclude? correct answers Compound is mutagenic without liver enzymes and this activity is further enhanced by liver enzymes Lynch syndrome is a human genetic disease characterized by ~100-fold higher incidence of colon cancer in men and women - and uterine cancer in women - by the age 50, as compared to the general population. Which statement below best describes the genetic cause of Lynch syndrome. correct answers Lynch syndrome is caused by defects in the human mismatch repair enzymes hMLH1 and hMSH2. Prokaryotic and eukaryotic ribosomes both contain RNA that functions as a catalytic enzyme correct answers True The wobble position in tRNA is 5' nucleotide in the anti-codon and 3' nucleotide in mRNA codon. correct answers True Ribosomal E, P, and A sites align tRNA anti-codons with the corresponding mRNA codons. correct answers True Accurate protein synthesis requires tRNA synthetases to link GTP to 3' end of tRNA molecules correct answers False Cells contain only ~30 tRNA molecules, of which 3 correspond to termination tRNA molecules. correct answers False Why are the BRCA1/BRCA2 genes considered tumor suppressor genes? correct answers Because BRCA1/BRCA2 encode DNA repair enzymes that normally prevent cancer mutations. Five different TATA Binding Protein (TBP) mutations are shown below. If these mutations were located in the region of the protein that is required for direct binding to the TATAA DNA sequence, which mutation would most likely be a conservative missense mutation that does not alter TBP function? correct answers Lys -- Arg Which of the following statements about pluripotent stem cells is true? correct answers They can develop into many different cell types under the right conditions. Choose the best answer that correctly identifies the labeled DNA and RNA sequences.Your choices for A, B, C, D, E are shown in the box correct answers X is RNA, Z is DNA coding, Y is DNA template. Which five statements below are correct regarding the process of prokaryotic DNA replication? correct answers 1. b-clamp keeps DNA Pol bound to DNA 2. DNA replication is semiconservative