microorganisms are one celled organisms, they include funi, bacteria and viruses. They are found in every living organisms. some microoganisms are harmful to the human body, these are called pathogens. However microoganisms can be jelpful to, some organisms need them to survive, they're also used in the food industry. For microbes to be visible they have to be grown in a lab under speacialised conditions. They're grown in agar jelly which is made out of the proteins from sea weed. Agar jelly is poured into a petri dish and left to set.