How does bacteria grow?
When people refer to bacteria growth it is actually talking about the amount of bacterium in a colony rather than the actual size of an individual bacterium increasing. Bacterium reproduce asexually through binary fission. This is when they basically just make a copy of their chromosome and then split. They reproduce sexually through conjunction. This is when they attach to one another using their pili, which are short hairlike structures on the outside of the cell. Through the pili they transfer a copy of a portion of their DNA. They then take on traits of the other cell. This helps to explain how bacterium can pass on drug resistance to one another.
1) Bacterial cells divide by binary fission (splitting into two cells) as often as every 20 minutes. 2) Generally the medium comes as a powder with agar included within the medium. There are directions on the label of the bottle for preparing a liter of medium. Once the medium is prepared, it has to be sterilized in an autoclave or pressure cooker. If the medium is to be plated, the agar is cooled and poured into the petri dishes. If the medium is to be tubed, it would be melted, dispensed and then autoclaved. 3) Agar in itself only acts as a solidifying agent. Other nutrients and buffers are present in the medium that supports the growth of the bacteria.
