CHAPTER 14 BIOL 2601 QUESTION EXAMPLES NOVEMBER 24 2025 1 A cell s ability to control its level of gene expression is called A gene transformation B gene regulation C gene splicing D gene addition E gene correction in the animal s condition is called a A transposable element B steady state gene C constitutive gene D recombinant gene E multifunctional gene 2 A genes expressed at a relatively constant level in tissues regardless of variations 3 Liver cells mammary cells and skin cells all contain the same genome however their respective proteomes vary drastically This observation is best explained by what phenomenon A gene splicing B cell division C cell differentiation D crossing over E evolution 4 Different globin polypeptides are expressed at similar levels during the embry 5 Events that occur during transcriptional regulation in eukaryotes include onic and fetal stages of mammalian development A True B False A DNA replication B mRNA translation C RNA modification and export from the nucleus D polypeptide synthesis E chromatin conversion to a closed conformation 6 Which of the following is NOT true of small effector molecules A They can cause a conformational change in a regulatory protein B They can prevent a repressor from binding a gene region C They can regulate gene transcription by binding to DNA D They can regulate gene transcription by binding a regulatory protein 7 What type of regulatory transcription factor binds DNA and increases the tran scription of a gene A a repressor exerting negative control B a repressor exerting positive control C an activator exerting negative control D an activator exerting positive control E a combination of both a repressor and activator exerting negative control 8 The ability of glucose to repress the lac operon depends on which effector molecules A allolactose B cAMP C tryptophan D ADP E starch A True B False A activated B repressible C inducible D coinducible E compressible 9 Small effector molecules directly bind the DNA they regulate 10 A n operon is one whose transcription is decreased by effector molecules 11 Genes organized into an operon are beneficial to certain bacteria because the operon allows for A differential regulation of individual genes that encode proteins that function B coordinated regulation of a group of genes that encode proteins that function C separate regulation of individual genes that encode proteins that function in D coordinated regulation of a group of genes that encode proteins that function E coordinated regulation of a group of proteins involved in numerous cellular in a common pathway in a common pathway different pathways in different pathways pathways Page 2 12 The lacA gene found within the lac operon encodes for galactosidase transacety group to lactose and lactose analogs lase This enzyme attaches a n A amino B hydroxyl C carbonyl D acetyl E carboxyl A polyintronic mRNA B polyextronic mRNA C polycistronic mRNA D polyexpressive mRNA E polyrepressor mRNA 13 An mRNA that encodes more than one protein is called a 14 The likely outcome from a mutation in the lacO site lac operator of the lac operon would be A binding of RNA polymerase could be hindered B binding of a repressor protein could be hindered C binding of the activator protein could be hindered D duplication could be affected E the order in which the genes of the lac operon are transcribed could be al tered lactose 15 The lacP site within the lac operon is upstream of the genes that encode for lactose uptake and metabolism proteins The lacP site is A the lac promoter site B where RNA polymerase binds C the site where genes are transcribed that encode proteins for metabolizing D the lac promoter site where RNA polymerase binds E the lac promoter site where genes are transcribed that encode proteins for metabolizing lactose 16 The event that occurs when allolactose levels increase in E coli is A transcription of genes within the lac operon increases B transcription of genes within the lac operon decreases C transcription of genes within the lac operon does not change D E coli cells replicate rapidly E the tryptophan operon becomes more active 17 In E coli cells when lactose is absent from the environment A large amounts of galactosidase lactose permease and galactoside transacety lase are made Page 3 B trace amounts of galactosidase lactose permease and galactoside transacety lase are made C no galactosidase lactose permease or galactoside transacetylase are made D the lac operon is induced E polycistronic mRNA levels would be very high 18 The lac operator site within the lac operon is an example of A a cis acting element B a para acting element C a trans acting element D an inter acting element E a contra acting element 19 A bacterium contains two copies of the lac operon one on the bacterial chro mosome and one on a plasmid The lacO site on the chromosomal lac operon is mutated and nonfunctional whereas the lacO site on the plasmid is functional What is the most likely outcome for the bacterial cell when glucose is declining and lactose is present A Expression of lac structural genes on the chromosome and plasmid will de crease because two copies of the lacO site are needed for repression of the lac operon B Expression of lac structural genes on the chromosome and the plasmid will increase because more repression of the lac operon occurs as glucose de creases C Expression of lac structural genes on the chromosome and plasmid will in crease because lactose is present and the repressor will not be bound to the operator D Expression of lac structural genes will not change because the lacO site is not involved in repression of the lac operon 20 When lactose becomes available the genes encoding galactosidase lactose permease and galactoside transacetylase are upregulated in E coli A True B False 21 What happens when the cAMP CAP complex binds the CAP site near the lac promoter A Transcription rate decreases B Transcription rate increases C RNA polymerase binds to the promoter D RNA polymerase binds to the promoter and transcription rate decreases E RNA polymerase binds to the promoter and transcription rate increases 22 A strain of bacteria containing F factor genes is called a A monozygote Page 4 23 A cis effect is a form of gene regulation that can occur between two DNA seg ments that are not physically adjacent A True B False 24 Jacob Monod and Pardee constructed a mutant strain of E coli that carried a lacI gene mutation encodes the lac