Restriction enzymes, which are extensively used in molecular biology, are products of bacterial "immune" system. Since bacterial genomes span several million base pairs (E. coli > 4 million bps), and the presence of restriction site within a genome is more than likely, how does a bacteria manage to protect itself from innate REs?

In iceland, the mid atlantic ridge runs through the center of the contry. what can you conclude about the apperence of iceland many thousands of years from now?

A. describe the scientific method, using pasteur's swan-necked flask experiment as an example.

You are studying several alleles of an e. coli helicase gene. one allele, called rsr, confers resistance to rs2014, an antibiotic that works by inhibiting helicase activity. bacteria with the rss allele are sensitive to rs2014. another allele, called ts-, produces a temperature sensitive mutation of the helicase. in bacteria with the ts- allele, helicase is inactivated at 42 °c but functions normally at 37 °c. helicase functions normally at both temperatures in bacteria with the ts allele. you obtain the following data while testing four strains of e. coli at different temperatures and doses of rs2014. each number represents the percentage of maximal dna synthesis. based on this data, assign the appropriate genotype to strains a–d in the spaces provided