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**Algae

But what exactly are algae? Algae is the name given to a large and diverse group of

oxygenic, phototrophic, eukaryotic microorganisms. Algae are eukaryotic, which means they

have a nucleus. This dierentiates them from Bacteria and photosynthetic yano!acteria.

 They are oxygenic phototrophs, meaning they use light as their energy source for growthand produce oxygen as a !yproduct, like plants.But what distinguishes algae from plants is

that algae do not have any tissue dierentiation. "lants can dierentiate their tissues into

roots, trunks, and leaves, all very dierent tissue types. #n contrast, algae are composed of

cells that are generally all the same.$espite the dierences !etween plants andalgae,many

algal species are closely related to plants. But the algae are very diverse. %ome algae, like

&uglena, are closer evolutionarily to single'celled proto(oa than to plants. The main unifying

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characteristic that determines if a species is considered an algae is that all algae contain or

have a very recent ancestor that contained chlorophyll a

)ungus like protist.They also reproduce !y forming spores. All fungus'like protists

are a!le to move at some point in their lives. There are essentially three types of

fungus'like protists+ water molds, downy mildews, and slime molds.

%temonitis is a kind of slime mold which forms small !rown !unches on the

outside of rotting logs. "hysarum polycephalum lives inside rotting logs and is a

gooey mesh of yellow threads that are several centimeters long. )uligo,

sometimes called -vomit mold, is a yellow slime mold found in decaying wood

/ater 0olds

/ater molds mostly live in water or moist soil. They can !e parasites of plants and

animals. They are a common pro!lem for farmers since they cause a variety of plantdiseases. 1ne of the most famous of these diseases was the fungus that caused the

#rish potato famine in the 2344s. At this time, potatoes were the main source of food

for many of the #rish people. The failure of the potato crop meant that many people