Humans their food, and they can’t live without

Humans can’t live without carbon,
nitrogen, protection from disease and the ability to fully digest their food,
and they can’t live without bacteria. (Maczulak, 2010) In soil and in the
ocean, bacteria play a major role in the decomposition of organic matter and
the cycling of chemical elements such as carbon and nitrogen, which are important
for human life.

Nitrogen is an essential element
for the building of amino acids; which are the building blocks of protein, and
nucleotides; which are the building blocks of nucleic acids like DNA and RNA. Nitrogen
is an important element, for humans because without it we wouldn’t have amino
acids and nucleotides. Our atmosphere is mostly made up of nitrogen, however
that gas cannot be directly taken in by living things, it has to be transformed
into a new molecule, in order to be taken in by living things and go through
the biotic part of the nitrogen cycle. So, that can be achieved through the
help of nitrogen-fixing bacteria. Bacteria are important for this process.
There are bacteria in the soil or root nodules that bring it in and make it in
the form of nitrates, then they’re able to be absorbed in the plant, and move
through the food chain, then decomposed through waste, and new bacteria turn it
into nitrates and these nitrates can be transformed into another sort of
bacteria and transferred into the nitrogen gas in the atmosphere. This can happen
over and over again.

Nitrogen-fixing bacteria; living in
soil or root nodules are able to take in nitrogen gas out of the air and
transform it into nitrates; this is called nitrogen fixation. Nitrate is
absorbed into plant life through the roots and then move through the community
by the food chain. In the plant, the nitrogen is in the form of proteins and nucleic
acids, those are going to ne eaten, broken down and re-assembled in animals,
then the animal produces waste, which decays and the nitrogen that’s in the
waste is in the form of ammonium. Since it’s difficult for plants to use ammonium,
bacteria break it down through the process of nitrification, this takes the
ammonium ions and nitrifying them, turning them into nitrates in the soil.
Since we need the nitrogen back in the atmosphere, another form of bacteria is used
for that. The nitrate in soil can be taken in by another species of bacteria
through the process called denitrification. These nitrates are turned into
nitrogen gas.

Bacteria have a key role in purification
of water. Bacteria from the Desulfobacteriaceae family are used to remove trace
minerals such as selenium, zinc, and even arsenic from the water making it safe
to drink. There are other microorganisms used to remove biological matter from sewage
by degrading the biological compounds through aerobic metabolism. Bacteria form
mineral deposits from water that surrounds them, binding them in the form of
tiny spheres. The bacteria bind zinc and sulphate, and they do it so effectively
that the zinc concentration in the spheres become a million times higher than
that in the surrounding water. This ability makes the tiny life forms
potentially very useful in the process of water treatment. The bacteria would
be used to remove zinc, selenium and even arsenic traces from the contaminated

Microorganisms such as Escherichia
coli are essential in the pharmaceutical manufacture. Many of the
pharmaceuticals are produced from the use of harmless microorganisms, such as
staphylococci, which are used to treat patients with disease such as tuberculosis
or syphilis by infecting them with such microorganisms. Many microorganisms are
used to produce vaccines that immunise the human body against them as well as
many different pharmaceuticals. They also play an important role in recombinant
DNA technology and genetic engineering.