A novel operon is controlled by two regulatory systems that function in a hierarchy. The first is positive repre and influenced by the presence or absence of maltose. The second layer over rules the first and is a negative inducible system influenced by galactose. Select which regulatory proteins would be bound to the operator wit this operon in the absence of both galactose and maltose and then choose whether or not the structural gene transcripts will be produced. (Choose all that apply) Structural gene transcription is ON The repressor is bound but the activator is not. The activator is bound but the repressor is not. Neither regulator protein is bound Both the activator and repressor are bound. Structural gene transcription is OFF

The regulation of the lac operon in E. coli by Catabolite Activator Protein and glucose is an example of what type of regulation? Group of answer choices Positive inducible Positive repressible Negative inducible Negative repressible Constitutive

You are doing a genetic engineering experiment. You use restrictions enzymes to cut the regulatory sequences from the lac operon and replace them with the regulatory sequences of the trp operon. Specifically, you will eliminate everything upstream of the beginning of lacZ and replace them with the trp sequences upstream of the beginning of trpE, including trpR. Now, describe the regulation of your ñew constructed gene. What will you do to get expression of the three lac genes? The lac Operon and its Control Elements lacl CAP P lacz lacY lacA genes 5 DNA binding site 3 AUG AUG AUG messenger RNA RNA polymerase blocked from transcribing trp operon Regulatory gene trp operon T PR Ptrp DNA trpR trpE trpD trpC trpB trpA Repressor bound to operator Promoter 5' trpR-MRNA R (a) Tryptophan present, repressor bound to operator, operon repressed. When complexed with tryptophan, the repressor protein produced by the trpR gene binds tightly to the trp operator, thereby preventing RNA polymerase from…

The symbols A, B, C, D, E represent all the components of the lac operon, excluding LacA. The symbols are not in the order of the lac operon. Minus and plus signs represent activity of lacZ or LacY in the absence or presence of IPTG. LacI+ or LacI-, and LacO+ or LacOC alleles were used. Which of the symbols represents each of the lac operon components?