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A mix of Saprolegnia asexual and sexual stages-no map

Saprolegnia showing a zoosporangium and a septum

A Saprolegnia zoosporangium

Saprolegnia antheridium and oogonium

A Saprolegnia oogonium containing zygotes (called oospores)
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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.
Saprolegnia is an example of a water_mold. Water molds have a superficial resemblance to fungi (sing: fungus) because they have a mycelium (pl: mycelia) composed of coenocytic_hyphae. Their body, however, is technically one huge multinucleate cell. Some have chitin in their cell walls. Others lack chitin and have cellulose instead. Some species have both chitin and cellulose. They have a cycle of alternation_of_generations and most are decomposers. Their group includes the causative agent of the Irish_potato_blight (Phytophthora_infestans) as well as Saprolegnia.
Oogonia (sing: oogonium) and antheridia (sing: antheridium) will develop from separate hyphae (sing: hyphus), then fuse to form a zoosporangium (pl: zoosporangia). A septum (pl: septae) is a dividing wall (cross wall) in hyphae.
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