Parasitic and Predatory Molds

Chytrids are saprobic decomposers or parasites of living organisms in muddy or aquatic habitats. They are single-celled species that produce motile spores that germinate on host cells. More complex species develop mycelia which are masses of absorptive filaments. Do not be surprised if you find the organisms in this group being called fungi. For many years, they were thought of as fungi, and still are by some.

Most water molds (Phylum Oomycota) are aquatic saprobes. Some water molds attack aquatic animals (such as goldfish) or land plants (such as Downy mildew which causes late blight of potatoes and caused the Irish potato famine.). They produce extensive mycelia, some of which become modified to form gamete producing structures. The diploid zygote develops into a resting spore that will germinate into a mycelium producing motile, asexual spores.

Slime molds are heterotrophic, free-living, amoebalike protistans. The cells are phagocytic (a cell that engulfs and consumes foreign material) and can aggregate to form a slimy mass that can migrate to find new food sources. Slime molds also disperse by spores released from stalk like structures.

There are two groups of slime molds:

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