Multicellular Algae

1. Multicellular Algae Lab Topic 14

2. Multicellular Algae • Photosynthetic protists are traditionally known as algae • An alga may be unicellular or multicellular • In this lab we will be concerned with multicellular algae • Phyla are characterized by • Cellular Structure • Pigmentation • All algae have chlorophyll “a” (as do plants) • Red and brown algae have accessory pigments

3. 14.1 C Phaeophyta (brown algae) • Chlorophyll “a” and “c” • Fucoxanthin – accessory pigment responsible for brown appearance • Almost all are marine • Largest and most complex, some have specialized conducting cells • Algin – a polysaccharide found within the cell wall of some brown algae. It is used as a thickening agent in commercial products • See Figure 14.5, observe the examples on display, and complete table on page 371

4. 14.1 F Rhodophyta (red algae) • Chlorophyll “a” • Phycocyanin and Phycoerythrin – accessory pigments responsible for some examples appearing red • Almost all are marine, mainly tropical • Unlike other algae, no motile cells in life cycle • Some examples have carbonates of calcium and magnesium in their cell wall and are important components of coral reefs • Agar – polysaccharide extracted from the cell wall of red algae • Carrageenan – also found within cell walls, used as a thickening agent • See Figure 14.9, observe the examples on display, and complete table on page 376

5. 14.1 F Chlorophyta (green algae) • Chlorophyll “a” and “b” • Fresh and marine environments • Believed to be the group from which plants evolved • See figure 14.10, follow the procedure on page 377, and fill in the chart at the top of page 378 • Be sure to answer all questions for all sections studied

6. Today’s Slides and Examples