1. Multicellular Primary Producers: Seaweeds and Plants

2. Multicellular Algae: The Seaweeds
Macrophytes or macroalgae
Multicellular, eukaryotic organisms
There are 3 types of seaweeds;
green
brown
red algae

3. General Structure of Seaweeds
Body of seaweed (thallus)
Leaf-like portions (blades)
photosynthesis
Gas-filled bladders (pneumatocysts)
Stem-like structure that provides support (stipe)
Attaches the thallus to the bottom (holdfast)

4. Fig. 6.1

5. Ulva or sea lettuce Green Algae Division Chlorophyta Freshwater Marine
Terrestrial
Bright green from chlorophyll
Ulva or sea lettuce

6. Codium

7. Brown Algae
Division Phaeophyta
Yellow-brown pigment, fucoxanthin
Temperate/polar
Rocky coast
Largest/complex
Fucus, rockweed

8. Kelp Largest of all brown algae Macrocystis Largest of the kelp
Grow 20in a day
Kelp beds are rich in life, most productive

9. Red Algae Division Rhodophyta Highest number of species
Red pigments; phycobilins
Parasite for other seaweed
Porphyra, rocky shores

10. Coralline alga
calcium carbonate in their cell walls.

11. Life History Reproduction asexual and sexual
alternation of haploid and diploid generation

12. Economic Importance Mariculture
Thick suspensions or gels at low concentrations (algin, carrageenan, and agar)
Dairy products such as ice cream and cheese
Frosting, Rx, shampoo, shaving cream, rubber products, paints, and cosmetics.

14. Flowering Plants Seagrasses
true marine species adapted to soft-bottom coastal regions
Members of the lily family evolved from terrestrial plants