What is the difference between positive and negative control? What is the difference between inducible and repressible operons?

How does cAMP and allolactose work to influence the operon?

What is not a part of an operon?

How is the operon positively and negatively regulated?

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?

For an enzyme to be produced from an inducible operon, the repressor must bind to and digest the substrate. the substrate must bind to the repressor and remove it from the operator. the substrate must bind to the operator. the repressor must be bound to the operator.

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.

The lac operon has which of the following characteristics? O 1) usually requires an activator protein bound to the promoter to be transcribed. O 2) is inactive in the presence of lactose. O 3) is active in the presence of a repressor. O 4) Is a constitutively active operator. O5) is only active in the presence of lactose.

What is an operon? Describe the functions of regulators, promoters,and operators.

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.