Horizontal gene transfer is a mechanism that allows bacteria to genetic information between cells. Describe this process.

Bacteria have a singular, large, circular chromosome and can have many smaller circular DNA-containing structures called plasmids. Bacterial cells that are in close proximity can form a connective bridge, called a pillus, which allows that passage of genetic material. Bacterial cell A copies the plasmid, through DNA replication, which it will pass to bacterial cell B. Instead of making it circular, it passes this plasmid copy through the pillus as a linear plasmid, which is then made circular when it reaches bacterial cell B. The pillus breaks and now there are two separate bacterial cells with the plasmid originating in bacterial cell A.