Question: highligt thebeneficial and harmful of bacteria to human being and ecosystem?

Rose Kigathi answered on 26 Jan 2017:

@abrb256 This is a heavy question. I assume you mean “beneficial and harmful effect”.
In microbiology we have a statement ” Microbes are everywhere!”.

And indeed they you have them in your mouth, on your skin, you breathe them in every day, you eat them every day. And they are very important. Your stomach for example contains numerous bacteria that allow you to digest your food, they enhance your immunity and on your skin they protect you from “bad” bacteria. Similarly in the ecosystem bcteria have more positive function than negative, they fix nitrogen, they cause decay of dead material helping recycle nutrients, they breakdown toxic materials and have been used even to digest oil in oil spills.

The main negative aspect in humans is their ability to cause disease. In the ecosystem negative effects are minimal except causing disease in plants and animals. Some bacteria can produce toxic chemicals that can harm an ecosystem, but this occurs rarely.