Chapter 7 Microbial Genetics Plasmids Circular genetic elements that reproduce autonomously and have an extra-chromosomal existence. ·1-1000 KB in size Typical plasmid 1/20 of chromosome Most are circular double-stranded DNA. some linear ds dna Transmitted from cell to cell via conjugation process Some can integrated into chromosome Can carry a variety of genes for production of toxin, resistance to antibiotics and heavy metals et al.Chapter 7 Microbial Genetics Plasmids • 1-1000 KB in size • Typical plasmid 1/20 of chromosome • Most are circular double-stranded DNA, some linear ds DNA • Transmitted from cell to cell via conjugation process • Some can integrated into chromosome • Can carry a variety of genes for production of toxin, resistance to antibiotics and heavy metals et al. Circular genetic elements that reproduce autonomously and have an extra-chromosomal existence: