how would removing the operator region from the e. coli tryptophan operon affect transcription of the trp enzyme genes? choose o
ne:a. transcription of the operon would begin normally but terminate prematurely.b. transcription of the aporepressor gene would decrease.c. transcription of the operon would be greater than normal in absence of tryptophan.d. transcription of the operon could not occur, and the cells would require tryptophan in the growth media.e. transcription of the operon would occur even if tryptophan were abundant.
Even if tryptophan was abundant, transcription of the operon would occur. By removing the operator, any impediment to transcriptional control is removed, and the operon is expressed under all conditions.
A nucleotide change in the sequence of the operator would result from a mutation in the trp operon's operator region.The trp operon responds to a repressor protein that binds to two tryptophan molecules. This repressor-tryptophan complex binds to the trp operator when tryptophan is abundant. Because this binding prevents RNA polymerase from binding, the operon is not transcribed. When there is little tryptophan in the cell, the trp repressor is inactive (because there is no tryptophan to bind to and activate).
the respiration rate will increase as temperature increases. An increase in temperature will minimize the amount of dissolved oxygen in the water and increase the metabolic rate of the goldfish, thus causing the goldfish's respiration rate to increase (“Hot waters make it hard for fish to breathe”).