What is the difference between vertical and horizontal transmission of antibiotic resistance between bacteria?

Vertical transmission occurs during asexual reproduction. During the cell cycle, a bacterium will replicate its DNA (found in the form of a circular plasmid) which will contain the gene for antibiotic resistance. Following a complete cycle of growth and division (ending with 'cytokinesis’ – the formation of a new plasma membrane) a daughter bacterium will have been produced that will also carry the resistant gene. Horizontal transmission occurs during a process called conjugation. Following the replication of the plasmid DNA, a donor bacterium will produce a pilus, a small projection that initiates contact with a recipient bacterium. A pore in the membrane of the recipient bacterium is then formed to create a continuous conjugation tube. The replica plasmid in the donor bacterium then becomes linear and can travel through the conjugation tube into the recipient, where it then becomes circular again. Thus, the recipient has acquired the gene for bacterial resistance.