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Originally, there were two subsections in the Protist (a/k/a Protoctista) kingdom: the Phylum_Protozoa (the animal-like protists) and the Division_Algae (the plant-like protists). Both groups were previously members of the animal and plant kingdoms, respectively. When you study zoology and botany, these groups will be included in the review of the animal and plant kingdoms. Since the early days of the Protist kingdom in the 1800’s a few more groups have been added to the kingdom, including the fungus-like (slime_molds and water_molds) protists.
Use pages 18-23 and 32-38 in the Photo Atlas as a reference for your review of the Protists. Recall that the authors of your Photo Atlas do not use the same exact method of classification as the authors of your textbook. Hence, the water molds and most algae are placed in the Protist group by your text authors, but not the Photo Atlas authors.
The Stemonitis are among the most distinctive of the acellular plasmodial slime molds. At one stage in their lives these organisms form a spreading, slimy coenocytic mass known as a plasmodium, which moves slowly over a substrate such as rotting vegetation.
When environmental conditions are altered, the plasmodium will grow stalks (columella) that support sporangia (sing: sporangium), which release mature spores.
A network of support tissues, termed the capillitium, extends outward from the stalk to support the clusters of sporangia. If the spores land in a suitable location after their release, they germinate and form single cells that use both flagella and pseudopods to move. These cells then fuse to form a new plasmodium.
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