**Classifying Prokaryotic Gene Expression****Positive Gene Regulation**- **Statement:** In the presence of the sugar arabinose, an activator protein binds the promoter of the genes responsible for processing arabinose and induces their transcription.- **Statement:** In the presence of lactose and low glucose, the lac operon is expressed 20-fold higher than in the absence of lactose.**Negative Gene Regulation**- **Statement:** In the presence of excess tryptophan, a repressor protein binds the operator of the trp operon and prevents the operon from being transcribed.- **Statement:** In the absence of lactose, the lac repressor protein binds the lac operon.- **Statement:** In the presence of iron, the dtxR repressor protein binds DNA, and the gene that encodes for the diphtheria toxin is not expressed.**Answer Bank:**1. In the presence of excess tryptophan, a repressor protein binds the operator of the trp operon and prevents the operon from being transcribed. 2. In the absence of lactose, the lac repressor protein binds the lac operon.3. In the presence of the sugar arabinose, an activator protein binds the promoter of the genes responsible for processing arabinose and induces their transcription.4. In the presence of iron, the dtxR repressor protein binds DNA, and the gene that encodes for the diphtheria toxin is not expressed.5. In the presence of lactose and low glucose, the lac operon is expressed 20-fold higher than in the absence of lactose.

Name: **Classifying Prokaryotic Gene Expression****Positive Gene Regulation
Uploaded: 2024-03-20T06:42:41.000Z
Channel: Bartleby
Description: **Classifying Prokaryotic Gene Expression****Positive Gene Regulation**- **Statement:** In the presence of the sugar arabinose, an activator protein binds the promoter of the genes responsible for processing arabinose and induces their transcription

positive gene regulation in the presence of lactose and low glucose , the lac operon is expressed 20 fold higher than in the absence of lactose. in the presence sugar arabinose an activator protein binds the promotor of gene responsible for processing arabinose and induces their transcription. Negative gene regulation in absence of lactose, lacR repressor protein binds to lac operon in the presence of excess tryptophan , a repressor protein binds with the operator of trp operon and prevents the operon became transcribed. in presence of iron the dtxR protein binds to DNA and the gene that encodes fir diphtheria toxin is not expressed.