Microscopic organisms, the most minuscule on the planet, the most numerous inhabitants of the earth - the bacteria.That there is at least surprising, is of interest to science since the invention of multiple magnify objects (microscope), they were finally seen by mankind.Before this took place the evolution of bacteria in humans, it can be said, "under the nose", but they have no one paid attention.And it is in vain!
ancient origin
They are the oldest inhabitants of our planet.Longstanding habitat of bacteria - the Earth.Bacteria were here first from living organisms, according to some scientists, about three and a half billion years ago (for comparison, Earth is approximately four billion).That is, roughly speaking, the age of the bacteria is comparable with the age of the surrounding nature.By the way, well-known history of mankind has only a few tens of thousands of years.Here we are "young" compared to these microorganisms.
Most small and numerous
Bacteria are also the smallest of all known representatives of wildlife.The fact that almost all cells of living organisms are of approximately equal size.But not bacterial cells.The average bacterial cell is about ten times smaller than the average cell, such as a human.Because they are so tiny and yet the most numerous inhabitants.It is known that lumps of soil where live bacteria may be as much inhabitants as, for example, people in every country in Europe.
Endurance
Nature, creating bacteria, put them in a huge margin, significantly higher than other endurance fauna.Since the "deep antiquity" a lot going on in the world cataclysms, and bacteria have learned to endure them.And still the habitat of bacteria is so diverse that causes a deep interest microbiologists.Microorganisms can sometimes be found in places where certainly none of the other creatures will not be able to dwell.
Where can live bacteria
example, boiling geysers, where the water temperature can reach nearly a hundred degrees above zero.Or - in the underground lakes of oil, as well as unfit for life acid lakes, where fish or any other animal would immediately dissolve - that is where bacteria can live.
Scientists suggest that some types of bacteria can exist even in space!By the way, these data are based on a version of the settlement of the globe living beings, theory of the origin of life on the planet.
Disputes
To endure these adverse conditions, some bacteria form spores.We can say that this is a special, sleeping, resting forms.Before forming spores, bacteria begins to dry out, removing itself from the liquid.It is reduced in size, while remaining within its shell, covered with an additional one shell - protective nature.As such, the microorganism can be a very long time, thus a kind of "waiting out" the difficult times.Then, depending on the environment in which they live bacteria - friendly or not - they can resume their livelihoods in full.This unique ability to survive in adverse conditions carefully studied by scientists, microbiologists.
Ubiquitous
the question "where the bacteria live?" Can be answered very simply: "Almost everywhere!" Namely, around us and in us, in the atmosphere, soil, water.And every day people come into contact with a myriad of creatures, without noticing it.Among them are pathogenic bacteria and opportunistic.There are quite safe for the human body.
on the ground in the soil, where bacteria live, they contain the greatest number.Here there are the nutrients necessary for life, and the optimal amount of water, there is no direct sunlight.Most of these bacteria - saprophytes.They are involved in the formation of a fertile part of the soil (humus).Here, however, there are also pathogens: agents of tetanus, botulism, gas gangrene and other diseases.They can then enter the air and water, after infecting these human diseases.
example, tetanus toxoid, rather large stick, is ingested from the soil at various skin lesions and multiplies in the anaerobic (without oxygen) conditions.
in water
Even where bacteria can live, so it's in the aquatic environment.Here they come, when they washes the soil and get into the sewage water.For this reason, by the way, artesian water is much less bacteria than in-ground.A plain water from a lake or river can become a medium where bacteria live, a place of distribution of many dangerous diseases: typhoid, cholera, dysentery, and some others.For example, dysentery caused by Shigella bacteria of the species and the body is accompanied by severe intoxication, shock syndrome.
The atmosphere in the air, where the bacteria can live, not so much as in the soil.The atmosphere is an interim step in the migration of micro-organisms, so it can not serve as - due to the lack of nutrients and lack of moisture - a permanent habitat for bacteria.The bacteria enter the air with dust, microscopic droplets of water, but then - deposited in the end, to the soil.However, in densely populated areas - metropolitan areas, for example - the number of airborne microorganisms can be high, especially in the summer.And the air itself can serve as a medium where live bacteria, all kinds of infections.Some of them are: diphtheria, whooping cough.As well as tuberculosis caused by tubercle bacillus.
per person
on human skin is a great variety of microorganisms.But they are not evenly distributed throughout the plane.There are bacteria "favorite" places, and there are sites that resemble desolate desert.And, according to scientists, the majority of microorganisms living on the skin of people who are not malicious.On the contrary, they perform a kind of protective functions of human germs, which are considered dangerous.It is scientifically proven that excessive sterility and purity - not so good (of course, the simple rules of hygiene has not been canceled).Least of all bacteria is the person behind auricles.The basic amount - on the forearms (where they were 45 species).A plurality of bacteria living in the mucous membranes, so-called wet areas where they feel very comfortable.In the dry (palms, buttocks) - living conditions are not very suitable for the micro-organisms.
within us
According to doctors, microbiologists, in the human gut is home to approximately three kilograms of bacteria!In quantitative terms - a huge army, with which to be reckoned.However, the bacteria - smart neighbors.The bulk of the dwelling in the human body (and other mammals) - useful and implement a peaceful neighborhood with the "masters".Some - help digestion.Others - perform security functions: as a result of their actions when pathogens attempt to penetrate the territory of the defendant immediately destroyed.99% of the population - Bifidobacterium and Bacteroides.A enterococci, Escherichia coli (which is conditionally pathogenic), lactobacillus - about 1 to about 10%.They are under adverse conditions can cause a variety of diseases, but in healthy humans perform useful functions.Yet there live various fungi and staphylococci, are also likely to be pathogenic.But mostly in the gastrointestinal tract there is some bacterial balance, like nature intended that supports human health at the proper level.A pathogens at a sufficiently high immunity can not penetrate inside and cause harm.
