Question

the trp operon in E.coli regulates genes that code for enzymes required for synthesis of the amino acid tryptophan. the trp operon is repressible operon. When tryptophan is not available in the enviroment, the trp repressor protein is (Active/Inactive/Regulated). Therefore, RNA polymerase can bind to the (Operator/Promoter/Structural Genes)

Answer 1

When tryptophan is not available in the environment, the trp repressor is inactive. Therefore, RNA polymerase can bind to the promoter.

Answer 2

Answer:

The correct answer will be 1. trp repressor protein is- inactive

                                          2. RNA polymerase can bind to the- promoter

Explanation:

A trp operon is a group of genes which encode for the production of the enzymes of amino acid tryptophan. It is a repressor protein and attenuation (coupled transcription and translation) regulated process which depends on the concentration of tryptophan in the environment that is when tryptophan is present in low concentration, trp operon is active while it is inactive in the presence of tryptophan.

In presence of tryptophan, the repressor binds to the operator of DNA sequence and thus blocks the path of RNA polymerase and terminate the transcription while in absence of tryptophan, repressor molecule remains inactive and RNA polymerase after binding to promoter sequence can promote the transcription of genes.

Thus, inactive and promoter is the correct answer.