Bacteria that can exist in salty environments are called halophiles . Obligate aerobes require oxygen. Facultative anaerobes grow well in oxygen, but can also grow without oxygen using the fermentation pathways. Obligate anaerobes grow without oxygen, and are harmed in the presence of it. Aerotolerant anaerobes cannot use oxygen for growth but will tolerate it.
Microaerophilic organisms grow in oxygen levels lower than that of the air.
Due to their small size, this process is difficult to observe. Indeed, growth in size of individual organisms is nearly impossible to detect. During this time, however, the individual cells are metabolically active and growing. They may be synthesizing inducible enzymes for use in the new medium. During this phase, the cells exhibit the most stable characteristics.