The lac operon produces: (choose the best answer) O A single mRNA molecule O A single protein O A single mRNA molecule and a single protein O Multiple proteins A single mRNA molecule and multiple proteins

Read the following statements about operons, and mark the FALSE one. O a. Prokaryotes use operons frequently because they are an efficient use of resources O b. The expression levels of the genes in an operon can be regulated individually Genes in an operon are placed next to each other (physically) O d. The genes in an operon share a single promoter

In the tryptophan operon, if the leader peptide is translated normally   A region 2 will pair with region 3   B a rho independent terminator will form.   C both a and b   D none of the above

What would occur if the repressor of an inducible operon were mutated so it could not bind the operator? Build up of a substrate wihin the pathway controlled by the operon Continuous transcription of the operon's genes Irreversible binding of the repressor to the promoter Reduced transcription of the operon's genes O O O O

segment of DNA segment of DNA reproesor profein RHA polymerase RNA polymerase rupraesor profin Dlagram A Dlagram B Which diagram shows a system in which the lac operon genes are NOT going transcribed by the E. Coli?

Place the components of an operon into the appropriate order                                                                                   Stop codon 2                                                                                   Promoter                                                                                   Start codon 1                                                                                   Stop codon 1                                                                                   Terminator                                                                                   Start codon 2                                                                                   Operator

All of the following statements about the repressor of the lac operon of E. coli are true EXCEPT which one? O A. The repressor is the product of a regulatory gene i The repressor binds to the operator region of the DNA of the lac OB. operon. The repressor is a protein. OC. The repressor interacts with the operator in such a way as to OD. prevent translation of beta-galactosidase. The repressor can combine with lactose to form a OE. complex that will no longer bind to the operator region. QUESTION 32 The amino acid which is a precursor of serotonin is Histidine OA. O B. Tyrosine O C. Glutamate D. Tryptophan O E. none of the above

A mutation that inactivates the repressor gene of the lac operon results in (a) the continuous transcription of the structural genes (b) no transcription of the structural genes (c) the binding of the repressor to the operator (d) no production of RNA polymerase (e) no difference in the rate of transcription

Figure 16.5 In E. coli, the tip operon is on by default, while the lac operon is off. Why do you think that this is the case?

A binding site for RNA polymerase is called a ________. a. gene c. codon b. promoter d. protein