Transformation is the process where bacteria take up a plasmid from the surrounding and then express the genes into proteins.  Scientists only want the genes expressed at certain times, so they control the expression using the operon system.  The arabinose operon is the classic system they use to control when the genes are to be expressed by the bacteria.  Arabinose is a sugar that can be added to the agar plate that will turn on the operon.   If arabinose is NOT present, no genes are expressed.   A. What type of operon system is this? ____(negative controlled or positive) Explain _____ B. What type of gene regulation is this____ (inducible or irrepressible) Explain: ____

Complete the table below by choosing a term(s) in Column B that associates with the term in Column A. Column A Column B Associated terms Repressor Activator Repressor & Operator RNA polymerase Corepressor RNA polymerase & Operon Promoter Operon & CRP LacZ CRP & Inducer Allolactose Inducer & Tryptophan Operator Tryptophan & B-galactosidase CAMP B-galactosidase & CRP binding site

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

What is the effect of a mutation in the allosteric site of the Lac Repressor protein? A) The Lac Operon would always be expressed whenever glucose is absent. B) The Lac Operon would never be expressed in any environment. C) The Lac Operon would be regulated normally. D) The Lac Operon would be never be expressed in lactose but would always be expressed in glucose.

Which of the following statements about operons are true? (Check all that apply) Operons are common in eukaryotes, but rare in prokaryotes. An operon encodes multiple (different) proteins. An operon encodes multiple (different) RNAs. An operon contains multiple promoters. The RNA produced from an operón contains more than one Shine-Dalgarno sequence. Operons often contain genes that function in a similar process so they are all turned on or turned off together. In other words, a mechanism to "coordinate" gene expression.

The next set of questions are all related to the following operon: This figure represents the ABC operon, which is a negative inducible operon, and its associated regulatory gene. The structural genes produced by the operon convert molecule A into molecule D. When molecule A is present in the environment, it will bind to the regulatory protein, and operon expression will be induced. operator testR T testR promoter regulatory protein testP testo structural genes test2 test1 T test1 test2 Where is the regulatory protein when there is NO transcription? test3 test3 structural proteins It is floating in the cytoplasm (not attached to the operon) with molecule A attached. It is floating in the cytoplasm (not attached to the operon) without molecule A. It is bound to the operator without molecule A. It is bound to the operator with molecule A attached.

If a wild-type (normal, NOTmutated) E. coli strain is grown in a medium: a. without lactose or glucose, how many proteins (and which ones) are bound to the lac operon? b. Without lactose, but with glucose, how many proteins (and which ones) are bound to the lac operon??

Regarding the tryptophan operon in bacteria, in the presence of tryptophan, tryptophan binds to the Group of answer choices Operon Operator Repressor Promoter RNA polymerase

When sequencing the genome of an organism and looking for potential genes, a sequence of DNA that would produce an RNA with a many bases between a start and stop codon is known as a promoter an operon an open reading frame a chromsome

If a researcher moves the promoter for the lac operon to the region between the beta galactosidase (lacZ) gene and the permease (lacY) gene, which of the following results would you expect? A) The three genes of the lac operon will be expressed normally. B) The repressor will not be able to bind to the operon. C) The operon will still transcribe the lacZ and lacY genes, but the mRNA will not be translated. D) LacZ will not be transcribed and Beta galactosidase will not be produced.