BIOL 222 Lecture Notes - Lecture 16: Hfr Cell, Plasmid, Long Term Ecological Research Network
Document Summary
Practice problem: 50% or more recombination frequency tells you they are un-linked. Bacterial reproduction: most undergo binary ssion. Rst dna duplicates, then cells grow and begin to divide, then daughter cells separate. Bacterial transfer of information: transformation = taking up information from the external environment, conjugation = contact dependent, using pili, transduction = dna exchange mediated by viruses. Transformation: avery dna is the transforming principle, cells must be competent in order to take up dna through transformation. Ex. expressing the right genes, etc: competency largely depends on environmental factors. Ex. temperature, stress, ionic conditions, nutrient availability, etc: if in unideal conditions, more likely to transform. makes sense, natural vs. arti cial transformation. Some cells are not naturally competent, some are: in order to get dna into cells which are not naturally competent, either treat the cells with chemical solutions, or give them an electroporation treatment.