Microorganisms like bacteria and fungi - mushrooms, molds and yeast - are often less visible, but at least as diverse as plants and animals. They have important roles in nature like the "recycling" of biomaterial. Many mushroom in symbiosis with plants. Even very resistant material like wood can be degraded by fungi with the help of very powerful enzymes.

 

Also we human beings cannot live without the bacteria on our skin and in our guts. We consist of ten times more bacterial cells than human cells! Only few bacteria are harmful and causes diseases.

Both fungi and bacteria are used in food production for thousands of years. Think of cheese, wine, beer, soya products, sauerkraut, and even salami. 

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