Transcript “red” algae
The Marine Microbial World and Multicellular Primary Producers CHAP 5 AND 6 THE STAR MEANS INFO. YOU NEED TO KNOW Classification: The Three Domains Domain Bacteria – Includes other members of old kingdom Monera – Has 1 kingdom – the Eubacteria Domain Archaea – Includes newly discovered cell types – Contains 1 kingdom – the Archaebacteria Prokaryotes: -No Nucleus Domain Eukarya – Includes all kingdoms composed of organisms made up of eukaryotic cells – Protista (debated/changing) – Fungi – Animalia – Plantae Eukaryotes: DNA in nucleus Categories within Kingdoms Kingdoms are divided into groups called phyla Phyla are subdivided into classes Classes are subdivided into orders Orders are subdivided into families Families are divided into genera Genus contain closely related species Species is unique Marine Microbes and Primary Producers Prokaryotes Bacteria Archae Unicellular Algae Diatoms Dinoflagellates Multicellular Algae Flowering Plants Protozoans Formaniferans Radiolarians Ciliates Fungi Red-Rhodophyta Green-Chlorophyta Brown-Phaeophyta True Plants Seagrass Salt Tolerant Mangroves Salt marsh grass Prokaryotes = “before nucleus” 2 Domains, 1 Kingdom each: Bacteria and Archaea (more closely related to Eukaryotes) Simplest and oldest life forms Cell wall, cell membranes No membrane bound organelles DNA not in a nucleus Great metabolic diversity Prokaryotes: Life Processes Various ways to obtain energy Autotrophs – “Self feeders” Use light or chemicals to create own energy Photosynthesis (light) or Chemosynthesis (chemicals) Light, Hydrogen Sulfide, Ammonium, Nitrate, Iron, etc. Heterotrophs – Cannot make their own food/energy must eat/ingest to get their food/energy Prokaryotes: Life Processes Various ways to break down and release this energy =Respiration Aerobic Organic matter broken down using oxygen to release energy Anaerobic Organic matter broken down in the absence of oxygen Bacteria Most abundant form of life on earth! Ensure the recycling of nutrients in detritis (VERY important!) Live in open water and sea floor, everywhere Accumulate on the ocean floor Large masses=marine snow Bacteria reproduction Bacteria reproduces by a process called binary fission. Binary Fission is where the bacterial cell divides into 2 cells that look the same as the original cell. Can reproduce every 20 minutes. Significance of Bacteria Ecosystem Significance Human Impact Break down organic Disease in humans material into nutrients for other organisms to use Cause diseases in marine animals Phytoplankton blooms Food spoilage Respiratory issues, rash. Toxins stored in shellfish, then humans eat it. Other Significance of Bacteria Symbiotic Bacteria = associates with other organisms closely. Parasites-harmful Beneficial, Live in a host organism Examples of Beneficial Wood-Digesting Bacteria in wood eating organisms Bioluminescence: attract mates, lure prey, communicate Examples of Parasitic Some toxic Ex: Cyanobacteria Photosynthetic Most abundant photosythetic org. in ocean Prob. 1st on planet Accumulated oxygen for Earth’s early atmosphere Many pigments to help capture light Chlorophyll-green Phycocyanin-blue Phycoerythrin-red Form stromatolites • mainly cyanobacteria • 2.8 bya in fossil record Cyanobacteria & Red Tide Unpredictable, unsure of cause. Massive blooms of phytoplankton Caused by cyanobacteria, dinoflagelletes, diatoms Harms marine life: -cuts fish gills, deplete oxygen levels, some poisonous/toxic Harms humans -toxic fumes cause sore throats, respiratory issues, eating marine life that stores these toxins-harmful/deadly Red Tide Fig 2. A series of phytoplankton blooms. A cyanobacterial (blue-green algae) in the Baltic Sea (upper left). Red tide bloom (dinoflagellate) in the Sea of Japan (upper right). Cyanobacterial bloom in the St John’s River Estuary, Florida (lower left). Cyanobacteriachlorophyte bloom in New Zealand (lower right) Archaea Ancient organisms – fossils found that date back 3.8 billion years Extremophiles – Found in extreme environments like hydrothermal vents and salt flats (two very extreme environments) Variety of metabolic types Widely distributed in the marine community They can tolerate wide ranges in temperature, salinity and even desiccation (drying out) Unicellular Algae (Alga, sing.) Eukaryotes-Protists (some animal-like/some plant-like) Membrane bound organelles = “little organs” Have a nucleus containing DNA Unicellular Cell Wall silicon in diatoms; cellulose in dinoflagellates Most photosynthetic, some heterotrophic Often animal-like Flagella Some heterotrophs Diatoms Photosynthetic Around half of the 12,000 known species are marine Yellow-brown from photosynthetic pigments Shell of silica Most important primary producer on Earth Oxygen & Bottom of the food chain Mostly solitary and unicellular, but some colonial Diatoms Used as filtration aid Mild abrasive in products including toothpaste Mechanical insecticide Diatomaceous Earth absorbent for liquids Cat litter Dinoflagellates Most 1,200 species live in marine environment Mostly photosynthetic, some can ingest particles Each species has unique shape reinforced by plates of cellulose Two flagella in grooves on body for motion Some are bioluminescent, produce light Zooxanthellae The corals and algae have a mutualistic relationship. The coral provides Zooxan. with a protected environment and compounds they need for photosynthesis. The Zooxan. produce oxygen and help the coral to remove wastes. Most importantly, zooxanthellae supply the coral with glucose, product of photosynthesis. The coral uses these products to make proteins, fats, and carbohydrates, and produce calcium carbonate Zooxanthellae provide corals with pigmentation. Left :healthy stony coral. Right: stony coral that has lost its zooxanthellae and has taken on a bleached appearance=“coral bleaching”. •If a coral polyp is without zooxanthellae cells for a long period of time, it will most likely die Dinoflagellates Symbiodinium sp. live in a symbiotic relationship with corals, sea anemones and other organisms (many of these host organisms have little or no growth without their symbiotic partner) Give products of photosynthesis to the host and in turn receive inorganic nutrients Noaa.gov Auburn.cedu Dinoflagellates A few species lack chloroplasts and live as parasites in marine organisms Pfiesteria produces very serious toxins that can cause massive fish kills, harm shellfish and impair the nervous system in humans. Whoi.edu Red tide Karenia brevis This toxic dinoflagellate is linked to dangerous “red tide” outbreaks in the Gulf of Mexico. Dinophysis Dinophysis species like these are associated with diarrhetic shellfish poisoning. Thalassionema Hundreds of diatoms can fit on the head of a pin, but these tiny organisms exist in countless numbers—enough to change seawater color during periodic population “blooms.” Significance of Unicellular Algae Ecosystem Significance Human Impact Protozoans= “first animals” Animal-like Unicellular Heterotrophs, ingest food BUT some photosynthetic! Found everywhere in oceans 3 main types: Foramaniferans Radiolarians Ciliates Protozoa: Foraminiferans Foraminiferans (forams) Exclusively found in marine community Found on sandy or rocky bottoms Shells of calcium carbonate Pseudopods (false feet) extend through pores in the shell where they are used to capture minute food particles such as phytoplankton Skeletons form sediment Foraminifera skeletons Can be important contributors of calcareous material on coral reefs or sandy beaches Pink sand in Bermuda Protozoa: Radiolarians Radiolarians Planktonic, mostly microscopic Shell of silica (glass) Like forams, they use pseudopods that extend through pores in the shell where they are used to capture minute food particles such as phytoplankton Ernst Haeckel: Challenger Expedition 1873-76 2775 species recorded Ciliates Cilia present for locomotion Hair-like Most projections live as solitary cells Some build shells made of organic debris May live on hard substrate Some are planktonic Significance of Protozoans Ecosystem Significance Human Impact Fungi Eukaryotic Mostly multicellular Heterotrophic Mostly decomposers Most of the 1,500 species of marine fungi are microscopic On mangroves, seagrass, sponges, shellfish, fish parasites. Biotec.or.th Fungi, lichen Like bacteria, many fungus break down dead organic matter into detritus Some fungus live in symbiosis with green algae, or cyanobacteria, these are known as lichens. Marine lichens often live in wave-splashed areas of rocky shorelines and other hard substrate Multicellular Algae: Seaweeds Eukaryotic Primary producers Not weeds, but algae. Most biologists agree that macrophyte is a much better name, macroalgae too. Lack true leaves, stems, and roots Physical Characteristics Thallus = the complete body Blade = leaf like, flattened portions Pneumatocysts = gas filled bladders, keep upright so towards sunlight Stipe = stem-like Holdfast = attaches seaweed to a substrate Thallus Macrocystis a. holdfast b. stipe c. blade - main organ of photosynthesis d. bladder - keeps blades near the surface Blade Bladder Stipe Holdfast Types of Algae Classes Chlorophyta = Green Phaeophyta = Brown Rhodophyta = Red Macroalgae: Green algae Have the same pigments as land plants (chlorophyll) More than 7,000 species Chlorophyta: Green Algae Halimeda opuntia Codium edule Caulerpa racemosa Caulerpa sertularioides Dictyosphaeria cavernosa Phaeophyta: Brown Algae Largest (size) and most complex of the algae Nearly all are marine (~1500 spp.) Brown color comes from accessory pigments (fucoxanthin) Padina (brown algae) with flat, calcified blades. Macrocystis pyrifera Sea palm (Postelsia palmaeformis) contains internal support structures that help them withstand wave action! Phaeophyta: Brown Algae Padina japonica Hydroclathrus clathratus Turbinaria ornata Sargassum polyphyllum Sargassum echinocarpum Kelps! Kelps are the largest seaweed we encounter in the ocean. They are also the most complex. Due to this large size, many of the kelps are harvested for food! Giant Kelp, Macrocystis pyrifera -The largest of the kelps. -anchors itself to the sea floor by use a massive holdfast. -extensive pneumatocysts used for buoyancy. -Pneumatocysts keep the seaweed close to the surface to maximize photosyhthesis Macrocystis pyrifera Macrocystis pyrifera These kelp obtain huge proportions growing as much as 0.5m/day! Kelp forest are great for sheltering all sorts of marine life, fish, invertebrates seals and sharks. And for food! Harvest of the upper sections of the blades for food. Division Rhodophyta “Red algae” Most in marine habitats 4,000 species • Members of the species Rhodophyta red algae, are more numerous than the green and brown algae combined (if we include aquatics). • Many red algae are in fact red. due to the presence of red pigments known as phycobilins, which mask chlorophyll. Porphya, a “red” algae Corallina, a coralline algae, deposits CaCO3 within its cell walls which provides structural support and often encrusting many surrounding surfaces. Rhodophyta: Red Algae Ahnfeltia concinna Acanthophora spicifera Galaxaura fastigiata Hypnea chordacea Asparagopsis taxiformis Products from Seaweed: Phycocolloids—form gels and increase viscosity of liquids Algin—stabilizer in ice cream (Macrocystis) Carageenan—emulsifier (Irish Moss, Chondrus) Agar—jellies (and of course all your plates in microbiology, Gelidium, Pterocladiella) Thickener and help smooth: • Many foods and milk-products Certain alga can be used to make agar or as stabilizer in gelatin and ice cream • • • • Toothpaste Beauty creams Paints Medical products- like bacterial culture plates, time-release pills, and dental impression gels Flowering Plants Flower, reproductive organ Photosynthetic Eukaryotes True stems, roots, leaves Dominant on Land, few Marine species True Flowering Plants: Seagrasses Salt Tolerant Plants: Salt Marsh grasses Mangroves --Seagrasses have rhizomes, or horizontal stems which grow beneath the sediment. --Provides habitat for juveniles and larvae of many marine species --Anchors sediments --Helps stabilize soft bottoms --Protects coast from turbulence and erosion Value of Seagrasses in FL (2006) Total value Florida for 6 seagrass dependent species ---$71.4 million. More than 70% of Florida's recreational and commercial fish, crustaceans, and shellfish spend part of their lives in shallow water estuaries. Shrimp industry --$28.2 million. Stone crab fishery--$13 million. Spiny lobster fishery--$18 million. Yellowtail and gray snapper--$3.1 million Over 30 species of tropical invertebrates dependent on seagrass habitats are collected in the Florida Keys for the marine collection industry yearly. Over $200 million spent yearly in Monroe County in the viewing of nature and wildlife. Salt Marsh plants Salt water tolerant species = halophytes Do not tolerate total submergence Act as water purification system Habitat and breeding grounds for many fishery species Protect against erosion Salt Marsh Plants Salt Wort Cordgrass Mangroves Mangroves Mangroves thrive in salty environments Able to obtain freshwater from saltwater. Some spp. secrete excess salt through their leaves while other block absorption of salt at their roots. Mangrove Impacts -Trap and cycle organics, chemical elements, sediment and minerals. -Leaf litter important for decomposition, recycling nutrients. -Provide shelter/habitat for marine organisms—often economically important ones. -Nearly all commercially/recreationally important fisheries spend a portion of life in mangroves and/or seagrass -Stabilize the coastline, reducing erosion from storm surges, currents, waves, and tides. Plate 8. Red Mangrove, Rhizophora mangle. Red Mangrove