Genetic transformation process by which free dna is incorporated into a recipient cell and brings about genetic change. Competent cell that is able to take up a molecule of dna and be transformed. Natural competence genetically programmed physiological state permitting the efficient uptake of macromolecular dna. Artificially induced competence state of competence achieved by chemical or physical treatment of cell: most bacteria are naturally competent. competence may be achieved at specific cell density quorum sensing. or if cells grown on particular surface. Gram positive = dna sequence binds, is fragmented, transported and degraded ssdna enters the cell. Gram negative = dna sequence binds, is framgneted, transported and degraded ssdna enters periplasm and hten into cytoplasm. It can be degraded or recombine into chromosome or plasmid by reca-catalyzed homologous recombination. Need dna uptake sequences: found in higher frequencies than expected. Dna import is active process that generates significant force.