Stramenopiles Photosynthetic Stramenopiles Ochrophytes Synurophyceans SilicaScaled Algae Tribophyceans

Stramenopiles

Photosynthetic Stramenopiles (Ochrophytes) Synurophyceans (Silica-Scaled Algae) Tribophyceans (Yellow-Green) Chrysophyceans (Golden Brown) Phaeophyceans (Brown Algae, Bacillariophyceans Kelp, Rockweeds) (Diatoms)

Brown Algae (Phaeophycean) Diversity Elachista Ectocarpus

Brown Algae Diversity Hormosira Scytosiphon

Brown Algae Diversity Fucus

Brown Algae Diversity Nereocystis

Brown Algae Diversity Streblonema Infected Macrocystis

Sexual Life Cycles I: Isomorphic Alternation of Generations Sporophyte (2 n) Scytosiphon Ectocarpus Gametophyte (n)

Sexual Life Cycles II: Heteromorphic Alternation of Generations Sporophyte (2 n) Macrocystis Nereocystis Laminaria (Kelp) Gametophyte (n) Sargassum

Sexual Life Cycles III: Diplontic (2 n) Fucus (Rockweed) (1 n)

Asexual Reproduction (2 n) Ectocarpus (1 n)

Brown Algae Ecological Significance Productivity: Up to 1 kg C / m 2 / y (Graham et al. 2008)

Brown Algae Ecological Significance 10

Brown Algae Viewing Sites Point Lobos State Preserve, CA (just south of Monterrey CA)

Brown Algae Viewing Sites

Brown Algae Economic Significance

Brown Algae Economic Significance Alginate

Growth Patterns: Diffuse (Non-Localized) Growth Fig. 14. 19 in Graham et al. 2008 Chorda filum

Growth Patterns: Apical Cell (Filamentous)

Growth Patterns: Apical Cell (Filament Bundles = Pseudoparenchyma) Desmarestia

Growth Patterns: Apical Meristem (Apical Meristem - Parenchyma)

Growth Patterns: Lateral Growth (Meristoderm)

Brown Algal Tissue Differentiation: Epidermis, Cortex and Medulla Laminaria Figs. 17. 15 in Lee 1999

Brown Algae Sugar Conducting Cells: (Trumpet Hyphae) Figs. 14. 45, 14. 46 in Graham et al. 2008

Brown Algae Organ Differentiation (Holdfast, Stipe, Blade)

Brown Algae Organ Differentiation (Pneumatocysts= Bladders) Sargassum Macrocystis Nereocystis

Brown Algae Organ Differentiation 7

Brown Algal Cell Structure

Cell Structure: Cell Wall 1

Brown Algal Cell Wall Characteristics: Plasmodesmata

Cell Wall Components I: Alginate Mg 2+ K+ Na+ Alginate Ca 2+

Cell Wall Components II: 3

Cell Wall Components I: Sulphated Polysaccharides

Brown Algae Herbivore Defenses: Physodes (Containing Tannins) 21

Brown Algae Plastids (PER) Fig. 12. 5 in Graham et al. 2008

Brown Algae Plastids (PER) Plastid Membranes Fig. 12. 5 in Graham et al. 2008

Brown Algae Pigments I

Brown Algae Pigments II Beta-Carotene 6 Fucoxanthin

Brown Algae Plastid: Pyrenoid 8

Brown Algae Storage Product: Laminarin Beta (1 – 3) Linkages

Brown Algae Cell Division

Brown Algal Cell Division (2 n) Ectocarpus (1 n)

Brown Algae Semi-Closed Mitosis

Brown Algal Cell Division: Cytokinesis

Brown Algal Life Cycles Sporophyte (2 n) Gametophyte (n) X

Isomorphic Alternation of Generations (Ectocarpus) Gametophyte (n) Sporophyte (2 n) Spore (n) Zygote (2 n) Gametes (n) Fig. 14. 23 in Graham et al. 2008

Unilocular Sporangium 11 Gametophyte Ectocarpus Sporophyte Pleurilocular Gametangium 12

Female Gametangium Male Gametangium Pheromone (= Sex Hormone) (e. g. , Ectocarpene)

Ectocarpus: Asexual Reproduction

Ectocarpus Summary Sporophyte (2 n) Gametophyte (1 n)

Heteromorphic Alternation of Generations (Laminaria) Sporophyte (2 n) Gametophyte (n 14 13 Zygote (2 n) Gametes (n)

Heteromorphic Alternation of Generations Sporophyte (2 n) (Laminaria) Gametophyte (n) Unilocular Sporangium Gametangia

Fucus (Air Bladders, Receptacles) 15

Diplontic (2 n) Life Cycle: Fucus Gametes (n) Zygote (2 n)

Diplontic (2 n) Life Cycle: Fucus Conceptacles, Ostiole, Female Gametangia, Male Gametangia 16 Fucus 17 Gametes (n) Male Gametangia Female Gametangia

Brown Algal Life Cycles Sporophyte (2 n) Gametophyte (n) X

Stramenopiles: Phaeophyceae 18 19