BioSc 231 General Genetics Exam 5 Name Multiple Choice 1 points each Which of the following is unique to eukaryotic gene expression A 5 polyadenylation of mRNA B Polycistronic mRNA C Coupled transcription translation D Removal of introns E Polysomes Which of the following statements is true regarding gene expression A The 3 end of mRNA corresponds to the carboxyl terminus of the protein B The first step is the association of mRNA with an intact ribosome C Involves proof reading of the mRNA D Prokaryotic RNA usually undergoes nuclear processing E Polypeptides are synthesized by addition of amino acids to the amino terminus Which of the following features is common to both DNA replication and transcription A Nucleotides are added to the 5 end of the newly synthesized strand B A sugar phosphate bond is formed between the 3 hydroxyl and the 5 phosphate C Deoxyribonucleotides are incorporated into the growing sequence D Both RNA and DNA polymerase require oligonucleotide priming E Both RNA and DNA polymerase initiate at promoter sequences Transcriptional activators A Do not require RNA polymerase to initiate transcription B Do not bind directly to DNA C Are essential for positively regulated gene transcription D Are short DNA sequences that increase expression of nearby genes E Are necessary for constitutive gene expression Constitutive gene expression refers to A Constant unregulated expression B Polycistronic mRNA C Coupled transcription translation D Mutant repressor that no longer responds to inducer E Gene expression following addition of inducer Which of the following statements is true A tRNAs are charged by binding to the ribosome B The anticodon of a tRNA hydrogen bonds to a codon C There are more distinct tRNAs than codons D All bases that can hydrogen bond are possible in the third position E tRNA has a 5 triphosphate Which of the following is unique to prokaryotic gene expression A Coupled transcription translation B Exon processing C 3 polyadenylation D mRNA capping E Promoter sequences Which of the following is true regarding gene expression A Only one gene can be present within a given DNA sequence B Mistakes in transcription are corrected by RNA polymerase C The ribosome binding site lies at the 3 end of mRNA D A change in genotype always results in a changed phenotype E A second round of transcription can begin before the preceding transcript is completed Which of the following is true regarding RNA processing A Spliceosomes are present in organelles and nuclei B Involves removal of exons C Involves removal of one or more introns D Occurs in prokaryotes E None of the above Which of the following occurs only in prokaryotes A TATA boxes B Self terminating transcription C Polycistronic mRNA D Coordinate gene regulation A negatively regulated genetic system A Is more common in eukaryotes B Requires an effector molecule acting at the promoter C Is derepressed by an inducer D Is completely off when repressor protein is present E All of the above To describe the genetic code as degenerate indicates that A mRNA is rapidly degraded B The code is not universal among organisms C Some amino acids have more than one codon D Frameshift mutations are tolerated E Stop codons may have corresponding tRNA molecules A positively regulated genetic system A Is derepressed by inducer B Is more common in prokaryotes C Must override an inhibitor D Is stimulated when protein bound with inducer interacts with the promoter E All of the above Which enzyme cleaves lactose to glucose and galactose A Lactase B Glucose synthetase C lactamase D galactosidase E glucosidase The product of the lacI gene A Is cis dominant B Cannot be complemented C Induces lac operon transcription D Binds to the operator E Transports lactose into the cell Normal self termination of transcription occurs due to the presence of A stem loop sequences in mRNA B Termination proteins C Multiple RNA polymerase molecules D Polyribosome formation Which of the following statements is true regarding tryptophan biosynthesis A It is controlled by attenuation and not repression B Translation controls transcription C A high tRNATrp concentration stalls translation at the ribosome D Tryptophan synthesis is regulated differently in eukaryotes and prokaryotes E It is non inducible Which of the following mutations may give rise to constitutive gene expression A Activator mutations B Operator mutations C RNA polymerase mutations D Enhancer mutations The lac inducer enables transcription by binding to A Activator B Lactose C RNA polymerases D Repressor E Operator Which of the following is characteristic of prokaryotic mRNA A Polyadenlyation of the 3 end of mRNA B Rapid turnover of mRNA C Removal of introns to form mature message D Formation of lariat structures E Capping of the 5 mRNA terminus The corepressor of tryptophan biosynthesis is A tRNATrp B Tryptophan C Tryptophanase D Tryptophan attenuator Which of the following is true regarding the machinery of translation A Initiation usually begins at an AUG codon B Eukaryotes have nuclear ribosomes C Polycistronic mRNA usually has a single ribosome binding site D tRNAs released from the ribosome are degraded E Termination is at inverted repeats The blastula is A A stage in embryonic development marked by cell migration B An infolded hollow ball of cells C An unfertilized egg D A ball of about 104 cells containing a cavity E A fertilized egg with no cleavage divisions An autonomous developmental restriction A is determined by genetically programmed changes in the cells B is imposed by the position of cells in the embryo C is mediated by physical interaction between cells D is mediated by morphogens Mutations that cause cells to undergo developmental fates characteristic of other types of cells are called A execution mutations B transformation mutations C transfection mutations D Programmed cell death Genes that function in the mother that are needed for development of the embryo are called A zygotic genes B developmental early genes C gap genes D maternal effect genes Genes that control early development through their expression in the embryo are called A zygotic genes B developmental early genes C gap genes D maternal effect genes The coordinate genes are maternal effect genes that A regulate expression of a small group of genes along the anterior posterior axis B determine the body plan at the level of segmentation C determine the body plan at the level of parasegmentation D establish