Where Bacteria Live

Bacteria live almost everywhere, even in conditions where other forms of life cannot survive. Bacteria are always present on the skin, and digestive and respiratory systems of humans.

And the answer to gaseous oxygen (02). Most bacteria can be placed into one of three groups based on their answers to 02.

1. Aerobic bacteria require oxygen to live.

2. Anaerobic bacteria cannot live in the presence of oxygen.

3. Facultative anaerobic bacteria can be either with or without oxygen.

B. Bacterial Lifestyle

1. Free floating bacteria

a. Bacteria can be free-floating. These free-floating bacteria also known as planktonic bacteria.

B. Until recently, most research on bacteria was carried out on a free-floating bacteria.

2. Attached bacteria

a. Bacteria can be attached to the surface and with each other. Communities of bacteria that are attached to each other and to the surface are described as living in biofilms.

B. When the bacteria attached to the surface, it activates a completely different set of genes that give the bacteria different from those it as free floating of the body.

c. It was estimated that more than 99% of all bacteria living on the earth as attached bacteria...