Key words Chromsome Plasmid Transposable genetic Elements Phage Lysophage(temperate), virulent phage prophage, lysogen /lysogeny Horizontal gene transfer Transformation transduction General transduction Lysogenic( specific) transduction/conversion Conjugation(transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells) F factor, Hfr, R plasmidKey Words Chromsome Plasmid Transposable Genetic Elements Phage -Lysophage (temperate), virulent phage prophage, lysogen /lysogeny Horizontal Gene transfer Transformation Transduction General transduction Lysogenic （specific）transduction/conversion Conjugation (transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells) F factor，Hfr， R plasmid