noun: microbiome; plural noun: microbiomes; noun: micro-biome; plural noun: micro-biomes
the microorganisms in a particular environment (including the body or a part of the body)."we depend on a vast army of microbes to stay alive: a microbiome that protects us against germs, breaks down food to release energy, and produces vitamins" the combined genetic material of the microorganisms in a particular environment."understanding the microbiome—human, animal, and environmental—is as important as the human genome”
The microbiome is the collection of all microbes, such as bacteria, fungi, viruses, and their genes, that naturally live on our bodies and inside us.
The human body provides a broad range of environments, and microbes are capable of living in all of them.
Each part of the body is a different type of ecosystem, like a planet with different continents and climates, the inhabitants of which have adapted to the characteristics of each location.
around nose and mouth
male and female urogenital
center of chest
Research suggests that bacterial population makeup and potential disturbances have links to:
Microbiota stimulate the immune system, break down potentially toxic food compounds, and synthesize certain vitamins and amino acids,  including the B vitamins and vitamin K. For example, the key enzymes needed to form vitamin B12 are only found in bacteria, not in plants and animals. 
Same number of BACTERIA in the gut as cells in the 70 kg “reference man” but that does not include the fungi, viruses and protozoa. There are many more organisms in our gut than cells in the body
Although there are supplements containing prebiotic fibers, there are many healthful foods naturally containing prebiotics. The highest amounts are found in raw versions of the following: garlic, onions, leeks, asparagus, Jerusalem artichokes, dandelion greens, bananas, and seaweed. In general, fruits, vegetables, beans, and whole grains like wheat, oats, and barley are all good sources of prebiotic fibers.