Explain what is Molds ?
Zygomycota, or molds, are a type of fungus made of filamentous hyphae that grow on decomposing material. The molds actually aid in the decomposition process. Airborne spores first settle on potential food, such as bread, or any other food source. If the right conditions exist - for instance warm temperatures and moisture - the spores germinate and produce filamentous hyphae, which send out running extensions called stolons. These stolons grow along the surface of a food, sending down rhizoids, which penetrate the food and aid in absorption of the nutrients.
The filamentous hyphae are colorless - what you might see on a food item in the refrigerator that has been left too long are black or green sporangia. Remember that hyphae are microscopic, which means that by the time you are able to see a "growth," there are thousands and thousands of filaments and black sporangia, each of which produce thousands of spores. Is it no wonder that any food that is left uncovered and exposed will eventually become infested?
One of the most common molds is the Black Bread Mold known as Rhizopus. Here below you see some typical sporangia and spores. Remember to always cover food and refrigerate!