Bumper sticker of the day: "It's as BAD as you think, and they ARE out to get you."


Review of Lecture 3: Monarchs of the sea: Algae


1. Algae - members of Kingdom Protista; base of aquatic food chains; plant-like but not plants.

2. Intertidal zone subject to extreme changes of environment - exposed to air and submerged. Green, Brown and Red Algae can all be found in the intertidal zone. (Review of Ulva -- can dry completely and survives exposure to air twice a day.)

3. Brown algae (Phaeophyta) -- ca. 1500 spp.; accessory pigment - fucoxanthin. Contains a mucilage in cell walls that prevent drying and functions as a shock absorber. Also the source of algin. Morphological parts - holdfast, stipe, blade. Examples - Fucus and giant kelps.

4. Red algae (Rhodophyta) -- ca. 4000 spp.; important reef builders; some unicellular forms have symbiotic relationships with animals; economically important.

5. Green algae (Chlorophyta) -- ca. 7000 spp.; unicellular, colonial, multicellular; marine, aquatic, and terrestrial habitats. Progenitors of land plants. Some unicellular forms have symbiotic relationships with animals or fungi.

6. Oligotrophic (low nutrient) and Eutrophic (high nutrient) lakes. Lakes develop over time from oligotrophic to eutrophic. Annual cycle involves turn-over of the water column layers; nutrient cycling; changing organisms over the year.

7. Pollution speeds up the eutrophication of lakes artificially.


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Last updated April 7, 1997.