Transcript Red tide
Plankton -Plankton are almost always at the bottom of the food chain in any marine environment, making them possibly the most important group. -The word “plankton” isn’t necessarily a technical science term, it is a general word to describe small organisms with no control over their long-term movements. -There are several groups and types of planktonic organisms. http://science.discovery.com/videos/brink-package-algae-to-oil.html Phytoplankton Diatoms – phylum bacillariophyta -Anywhere from 5,000 – 50,000 species estimated. -More than 1 million diatoms can be created from 1 diatom in just 2 weeks. -Make up 25% of photosynthetic biomass on Earth. *Bilateral or Radial symmetry *Frustule - two-part silica skeleton. One layer sits outside of the other, sort of like the lid of a petri dish raphe *Secretes a “mucous” through the raphe, long slit down the center of a diatom Phytoplankton Dinoflagellates - Dinophyta *2nd largest group of photosynthetic algae, behind diatoms. *Very few of them are heterotrophic parasites in fish. -Small movements by means of flagella, protein appendages that flip back and forth -Red tide phenomenon is caused by dinoflagellates. Its an overgrowth caused by excessive nutrients, water is reddish brown due to tons of dinoflagellates in water. (up to 20 million per liter) pictures on next slide. -Many species are bioluminescent when disturbed. “……it is not the property of fire alone to give light;…small drops of the water, struck off by the motion of the oars in rowing, seem sparkling and luminous.” Francis Bacon, 1605 Plankton - Red Tides -Large amounts of dinoflagellates turn the water reddish-brown, and make it poisonous to humans and other organisms who live in the water. Off the coast of California Red tide off coast of Washington State -These produce high amounts of potentially deadly neurotoxins. Phytoplankton *Mutualism between coral and dinoflagellates Phytoplankton Green Algae – Phylum Chlorophyta *When you typically think of seaweed, this is what you are actually thinking of. *Photosynthetic, mainly multicellular in marine ecosystems. *Scientists believe that land plants may have evolved from green algae due to having similar types of cholorphyll. *Produce cellulose (makes cells rigid and hard). *Different in that green algae lack roots and transport structures (xylem and phloem). -Some species also have mutualistic relationships with coral and other cnidarians (jellies). Phytoplankton Red Algae – Phylum Rhodophyta *Similar to green algae, except they have no cellulose, but some do secrete calcium carbonate. *Do NOT produce the same types of chlorophyll as land plants and green algae. *Some secrete calcium carbonate (act like cement in a brick wall). *Phycoerythrins – red pigments produced by red algae. NO OTHER EUKARYOTE contains these pigments. ***They can live in deeper water because they absorb blue light, which travels further than any other color on the spectrum. Phytoplankton Brown Algae – Phylum Phaeophyta *Most complex structure of all types of marine algae. *Can have holdfasts (roots), blades (leaves), stipes (stalks), pneumatocysts (air-filled chambers to keep near light). *Kelp can reach the surface from nearly 80 feet deep (grow almost a foot a day). Sargasso Sea (Center of North Atlantic) – named because of so much floating brown algae (sargassum is a genus of brown algae). Amoeba/Paramecium Amoeba – eukaryotes, engulf their food using phagocytosis Paramecium – eukaryotes, move using cilia, tiny hairs. Hairs also push food into mouth-like opening. Zooplankton Copepod - plankton from Spongebob Phylum Arthropoda Daphnia – water fleas (look like pregnant birds) Planaria – flat worms, 2 eyespots. Krill – closely related to shrimp, one of the most abundant animals in the sea. Phylum cnidaria – hydra, smaller sea anemone Ostracod – swim in circles with long appendages Nematodes – Phylum Nematoda -These are extremophiles, meaning they can survive in extreme environments. -They can live in incredibly hot or cold habitats and can survive on almost no food for weeks at a time. -Tens of thousands of species have been identified, most of which are parasitic. Nematode digestive infection Why are these all so IMPORTANT? BOTTOM OF THE FOOD CHAIN!!!!!!!!!!!!!