Those that spread along the surface are called stolons. At intervals along the stolons, clusters of shorter hyphae, called rhizoids, extend down into the food supply and secrete enzymes that break down sugar and starch into digestible food. The rhizoids absorb the food, and water as well. Molds can reproduce both asexually and sexually. When mature, the sporangia break open and release their spores, which will germinate if they reach a suitable environment.
Sexual reproduction is accomplished through a form of conjugation.
Two different mating types of hyphae, termed plus and minus, form short, specialized side branches. If the tip of a plus branch meets the tip of a minus branch, conjugation occurs. Each tip becomes a gamete cell, with two fusing to form a zygote. The zygote matures into a zygospore, which may germinate after one to several months if conditions are favorable. Some molds, like water molds, live on the bodies of dead insects and other animals in the water.