Write in detail about Plasmids.

Explanation

Plasmids are extrachromosomal double stranded, circular , self-replacating, autonomous elements. They contain genes for fertility, antibiotic resistant and heavy metals. It also help in the production of bacteriocins and toxins which are not found in bacterial chromosome. The size of a plasmid varies from 1 to 500 kb usually plasmids contribute to about 0.5 to 5% of the total DNA of bacteria. The number of plasmids per cell varies. Plasmids are classified into different types based on the function. Some of them are F (Fertility) factor, R(Resistance) plasmids, Col (Colicin) plasmids, Ri (Root inducting) plasmids and Ti (Tumour inducing plasmids).