Bacteria are responsible the
decomposition process the end of
chains and food ; in this
process, also liberate utile
and nutrients for living beings.
Bacteria live within the
tube of ruminants of some insects
cellulose for these . Some
bacteria also in the nitrogen
, making fixation of ,
nitrification and denitrification,
always in mutualist
interaction with plants.Bacteria
within living beings, example, some
that inside the bowels,
with other pathogenic so
controlling the of noxious
agents.There also bacteria that
diseases and bacteria in the
production medical drugs.

Excessive or mass
destruction bacteria can impact
ecosystems. For example, a river
is by organic material
population of aerobic increases
since the material isfood for
; the great number bacteria
then exhausts oxygen dissolved in
and other aerobic (like
fishes) undergo death.