Fungus-like Protists

    Fungus-like Protists are the group of water and slime molds. The fungus-like characteristics have structure to produce spores, heterotrophic, parsitic, or act as decomposers. As decomposers, they produce enzyms that break down or convert organic materials from dead organisms and absorb them in the form of inorganic materials.

Water Molds (Oomycota)

    There are 580 known kinds of water molds that act as decomposers in aquatic habitats. Most of them are free-living and obtain their nutrients from the remains of dead plants in ponds, lakes, and water streams. Some live inside dead tissue of plants, and some others are parasites of other aquatic organisms, for example Saprolegnia. It attaches itself to fish or other aquatic organisms. Saprolegnia has layers of membrane.

    There are also other water molds that are pathogenic to plants, for example white molds (Plasmopara viticola) that grow in colonies on grapes. Another example is the wilting and rotting potato plants and tomato plants that is caused by the water mold Phytophthora infestans.

    Water molds can reproduce sexually or asexually. It reproduce asexually by forming sporangium at the tip of their hyphae structures (filament or thread). Sporangium will be filled by flagellated spores (zoospores) that will be released when they mature. When spores fall on an optimal environment, they grow to become new mycelium.

    Sexual reproduction occurs by the meeting of male and female gametes. Gametes are produced by differenttiated hyphae. Male gametes are produced by antheridium, and female ones by oogonium. Fertilization between gametes produces diploid zygotes that grow into thick-walled spore which then will grow into new mycellium.

Slime Molds (Myxomycota)

    All slime molds produce free-living cells during part of their life cycle. These cells are called amoeboid because of their resemblance to Amoeba. Like the real Amoeba, slime molds are phagocytic predators because slime molds can ingest bacteria, pests, spores, and other organic components.

    During times of low food availability, hungry cells combine themselves together to form a slimy mass. This mass migrates to a new environment with more favorable conditions to support their growth. The mass motion is derived from the acculumulative force of contraction from each single cells. An example of a slime molds is Dictyostellium discoideum.