Astrain of bacteria possesses a temperature-sensitive mutation in the gene that encodes the sigma factor. the mutant bacteria produce a sigma factor that is unable to bind to rna polymerase at elevated temperatures. what effect will this mutation have on the process of transcription when the bacteria are raised at elevated temperatu

The process of transcription will b stopped. Sigma factors are responsible for determining the specificity of promoter-DNA binding by polymerase and control how efficiently RNA synthesis (transcription) is initiated. High temperatures probably interfere with the structure of the sigma protein and change the conformation of the active site that binds to the rna polymerase.   

which

what is a measurement of the earth’s history divided into time periods?

> fossil record <

sedimentary rock

> geologic time scale <

radioactive elements