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The fungi include a variety of general forms–yeast, mold, mushrooms, and imperfect fungi. They reproduce in a variety of ways by a bud arising from a parent yeast cell, by the addition of a vegetative cell to chains of cells called hyphae, and by the production of both asexual and sexual spores.  Although fungi form both asexual and sexual spores, they are classified based on the type of sexual spore they form.

Zygomycetes produce sexual spores called zygospores, which are formed from the fusion of hyphae of two different mating types. Some species of Rhizopus are responsible for producing zygomycosis.  Inhalation of spores leads to invasion of the blood and eventually necrosis of tissues, especially in diabetic and immunocompromised individuals. A single mating type of Rhizopus produces dark-colored structures called sporangia. Each sporangium contains many asexual sporangiospores. Rhizopus is a common bread mold, its hyphae are haploid and non-septate (coenocytic), and cytoplasmic streaming within them is common.  Surface hyphae called stolons are anchored by rhizoids where the hyphae contact surfaces. Asexual sporangiospores are produced by sporangia at the end of elevated  stalks  called  sporangiophores. These spores develop into hyphae identical to those that produced them. 

Sexual reproduction occurs when hyphae of different mating types (+ and - strains) make contact. Progametangia extend from each hyphae and upon contact a septum separates the end of each progametangium into a gamete. The walls between the two gametangia dissolve, the gametes fuse and a thick-walled zygospore develops. The zygospore germinates and produces a sporangium. Haploid spores are released that develop into new hyphae, and the life cycle is completed.