Atmospheric requirements of different bacteria

http://www.bmb.leeds.ac.uk/mbiology/ug/ugteach/newdental/introduction/bacteria/bacteria_atmosphere.html

-Test-tube (i) shows an obligate anaerobe, unable to grow in the presence of oxygen, close to the surface of the growth medium

Test-tube (ii) shows an facultative bacterium, which is indifferent to the presence of oxygen.

Test-tube (iii) is an obligate aerobe which can only grow at the surface of the medium.

Test-tube(iv) is a microaerophile that can only grow where the oxygen level is low.
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Microorganisms like bacteria can be classified by their relationship to Oxygen.
Different bacteria isolate has different atmospheric requirements.
The classification involves 5 major groups, the obligate aerobes,microaerophilic aerobe,facultative anaerobe,aerotolerant anaerobe and obligate anaerobe

>Obligate aerobes strictly need oxygen to survive which means that in the absence of Oxygen they would die immediately.

>Microaerophilic aerobe bacteria would be killed when exposed to normal atmospheric levels of oxygen,but yet still requires traces amount of oxygen to grow.

>Facultative anaerobe can survive in both the absence and presence of oxygen.

>Aerotolerant anaerobe do not require oxygen

>Obligate anaerobe die in the presence of oxygen