Populations Unit: Marine Algae NSF Grant DRL-1316782

Marine Algae

Think … Pair … Share To which kingdom do you think algae belongs and WHY? Explain how algae get their energy? What are some examples of marine algae?

Kingdom Protista & Plantae They lack true leaves, stems, and roots Most are photosynthetic Include: Bacillariophyta (Diatoms) Dinophyta (Dinoflagellates) Chlorophyta Rhodophyta Phaeophyta

Basic Structure of Marine Algae Pneumatocysts Thallus

Thallus is the complete body and all portions can photosynthesize Kelp Forest, California

Blades are leaf-like portions - increase surface area - no veins Common Sea Lettuce

Macrocystis pyrifera Giant Kelp Some algae have pneumatocysts, or gas-filled bladders allowing the seaweed to stay at the surface Cool Fact: some pneumatocysts contain carbon monoxide (CO) Macrocystis pyrifera Giant Kelp

- Some algae have a stem-like structure called a stipe Giant Kelp

- in some seaweeds holdfasts are structures that secure the thallus to the bottom

2 3 1 blades stipe holdfasts Several sea palms at the Pillar Point Marine Reserve.  Half Moon Bay, San Mateo, California 3 stipe holdfasts 1 List the name of the part and it’s function 1. 2. 3.

Divisions of Algae-classified by pigment * Glaaucophyta = freshwater *Xanthophyta = almost all freshwater

Division Rhodophyta Red algae Multicellular Important to coral reefs because it helps cement the reef together Phycoerythrins- red pigment which allows red algae to live deeper in the water Chelidonura Sea Slug

Examples: Irish Moss (left) and Nori (right) Most abundant and widespread macro-algae with over 4,000 species Examples: Irish Moss (left) and Nori (right)

Division Chlorophyta Multicellular Green algae and land plants have chlorophyll a&b Chlorophyll a- absorbs different colors of light and used for photosynthesis Chlorophyll b- helps to capture light Cell walls made of cellulose

Cladophora sericea-Invasive species on West Maui, Hawai’i Chlorophyta Examples only 10% of all 6,000-7,000 species are marine some species are endophytes, or plants that live within the tissues of other plants Cladophora sericea-Invasive species on West Maui, Hawai’i Sea  Lettuce

Division Phaeophyta Brown algae varies from olive-green to dark-brown in color due to yellow pigments Multicellular Holdfast- anchors the plants Blades (like leaves) Pneumatocyst: gas-filled bladders

Phaeophyta Example Kelp is the most complex group of brown algae https://www.youtube.com/watch?v=4-Qj_LCae8A Phaeophyta Example Kelp is the most complex group of brown algae harvested for food in some parts of the world can be 100 m long and grow to 50 cm per day -Why does it need so many pneumatocysts? form kelp beds or kelp forests in colder waters of the N. and S. Pacific Diver in Kelp forest at Ship Rock Catalina Island, California Kelp harvester in California

Sargasso Sea Nuestonic community (organisms that float on top of the water) Drifting rafts of sargassum (brown algae) Found in the North Atlantic Ocean (in the gyre) Question: What are the biotic and abiotic factors that would affect this area?

Cyanobacteria Also known as blue-green algae Photosynthetic Major producers – produce most of Earth’s oxygen Unicellular Prokaryotic cells No true nucleus Hyella stella: lives in Marine Limestone

Diatoms Unicellular, Golden colored, some free-floating others colonial Most productive phytoplankton Cell walls made of silica

Diatoms Examples Coccolithophores – often used to study climate change, ocean acidification, & eutrophication Diatom bloom- sudden increase of diatoms usually during summer when there is an increase in nutrients

*from Greek meaning “flame-colored” Dinoflagellates *from Greek meaning “flame-colored” Unicellular Use flagella to swim 2nd most productive group of primary producers

Noctiluca & Symbodinium Dinoflagellate Examples Noctiluca & Symbodinium

Dinoflagellate Algal Blooms Algae Blooms Toxins: Ciguatera: causes seafood poisoning (red snapper, grouper) HABs (Harmful Algae Blooms) *cause Red Tide Overabundance of algae that is harmful to the marine organisms, humans, a environment.

Bioluminescence the production and emission of light by a living organism as the result of a chemical reaction during which chemical energy is converted to light energy. Found in the dinoflagellates Ninety percent of deep-sea marine life is estimated to produce bioluminescence in one form or another.

 Bioluminescent algae Noctiluca Scintillans at Camp Cooinda on the Gippsland Lakes

https://www. youtube. com/watch https://www.youtube.com/watch?v=uUbIWqiynBY&list=PLTSht9sGRj-qCNlB2YrhVBrSO6OGaxvDw&index=10 https://www.youtube.com/watch?v=Fvob6L8q3I8&list=PLTSht9sGRj-qCNlB2YrhVBrSO6OGaxvDw&index=9

Importance of Marine Algae Oxygen production (90%) Habitat Food Marine Organisms Human Gelatin (thickening agent) Toothpaste Sushi