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May 26 Please submit a question about your presentation Division: to me electronically. blue-green algae May 28, June 2 & 4 -Student Presentations Powerpoint Presentation 7-9 minutes. Both people must speak during the presentation. Intro, Material & Methods, Results & Discussion

May 29Turn in herbarium early- 10 points extra credit Mastocarpus papillatus complex (C. Agardh) Lindstrom Ulotricales/Ulvales-3

June 4/5- Lab practical, Notebooks & pressings due!

June 11- Final 8:00-11:00am Single class: Cyanophyceae ~4,484 species 1 2

Algal : Groups () 1.- cyanobacteria (blue green algae) 3.9 bya = Cyanobacteria appear and introduce 2.Archae 3. 1. Alveolates- 2.5 bya = Eukaryotes appeared (nuclear envelope and ER thought to come from invagination of plasma membrane) 2. Stramenopiles- , heterokonyophyta

1.6 bya = Multicellular algae -Rhodophyta () & 3. Rhizaria- unicellular amoeboids (Green algae) 4. Excavates- unicellular flagellates

900 mya= Dinoflagellates & Invertebrates appear 5. Plantae- rhodophyta, chlorophyta,

490 mya = Phaeophyceae (Brown algae) & land & coralline algae & 6. Amoebozoans- slimemolds crustaceans & mulluscs 7. Fungi- with extracellular 408mya= Insects & Fish 8. - unicellular 362 mya = Coccolithophores & Amphibians & Reptiles 9. - multicellular heterotrophs 290mya- Gymnosperms 4 145 mya = Diatoms & Angiosperms

1 Domain Bacteria- unicellular, lacking a nucleus, , tRNA, peptoglycan in the wall Cyanobacteria are important because:

Phylum Low-GC Gram-positive- staph & antrax High GC- Gram-positive- & • Cyanobacteria are modern representatives of the very Phylum Hyperthermophilic bacteria- live at high temperatures Phylum Hadobacteria-live at high temps, consume nuclear waste first photosynthetic on . Phylum Cyanobacteria- blue green algae, origin of the Phylum Spirochetes- & lime •First organisms to have 2 photosystems and to produce Phylum - intercellular parasites orggganic material and to give off O2 as a biproduct. Phylum - , nitrogen fixers, , origin of mitochondria •Instrumental in transforming early atmosphere to an oxidizing one  the revolution

• Most common algal group in terrestrial systems and symbiotic relationships

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Cyanobacteria Cellular Structure Cyanobacteria Cellular Structure •Nucleus ? – none, circular DNA, lack No complex

Thyllakoids- photosystems I & II

? – no complex organelles Carboxisomes- bacterial microcompartments that contain - single or paired involved in -concentrate CO2 for RuBisCo •Pigments?– Chl a, b, d - B carotene phycobiliproteins- phycoerythrin, phycocyanin, allophycocyanin •Carbon storage? - Cyanophycean starch •Flagella ? –none • History? Asexual

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2 Cyanophyta Cellular Structure Cellular Structure: microscopic vegetative cells- photsynthesize • Unicells in envelope spores- resting stages

• Colonies heterocysts- specialized cells for fixing nitrogen

• Filaments, Branched filaments most complicated form

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“facultative chemoautotropes” Morphology of Cyanophyta • made of , polymer consisting of sugars and •Many spp have the ability to photosynthesize under both aerobic amino acids (not ), similar to gram-negative bacteria and anaerobic conditions • Trichome- Row of cells Difference is where the come from: • Filament- Trichome within a mucilaginous sheath

Aerobic conditions? donor is Water O2 produced • MiliMucilaginous ShhSheath- layer of mucil age outs ide of ce ll wa ll

C02 + H20 CH2O + O2

• Possible to have > 1 trichome within a filament Anaerobic conditions? is sulfide  Water is produced

CO2 +2H2S CH2O + 2S + H2O

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3 Mucilaginous Sheath – False branching = True branching = –motion (gliding) outgrowth of filaments outgrowth from cells that -protection against desiccation adjacent to dead or change their axis of - protection against UV irradiance specialized cells; filament division, 90 degrees from curves axis of trichome

Sheath is often colored: Red = acidic Blue = basic Yellow/Brown = high salt

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Buoyancy: Movement Cells contain gas vesicles or gas = hollow cylinders made of 1. ”Gliding” against a solid substrate -no change in shape or obvious pushing; no ability to steer, sometimes trichome rotates within •low light? Decreased Ps  of  sheath, and sheath is left behind as the trichome moves forward increase in gas  float upward

2. Jet propulsion = excrete mucus •high light? Increased Ps  Accumulation of polysaccharides  cell pressure increases  gas vacuoles shrink  sink 3. Helical species (e.g. ), use waves of contraction

4. Swimming? No idea how they do this, but evidence of and .

5. Changing buoyancy

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4 Reproduction: Reproduction 4. Hormogonia = short piece of trichome that detaches from parent filament and glides away  No sexual reproduction  some DNA transfer has been observed, not conjugation per se.

through:

1-Binary – dividing in two HiHormogonia

2-Fragmentation of colonies Separation disk or “Necridium” = funky dead cell where detachment occurs

3-/exospores

4-Hormogonia

5-Akinetes

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Reproduction Akinete 5. Akinetes = thick-walled resting spores. Packed with reserves; dense = sink to the bottom when released. Triggered by unfavorable conditions, can remain viable for years.

H A - akinete

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5 Earliest evidence of Cyanobacteria comes from : Wide Range of - 3.5 BYA

•Freshwater lakes

•Terrestrial hotsprings at Yellowstone Park

• Marine systems (intertidal, open )

• Extreme environments (e.g. salt flats, hot springs, glaciers, etc.)

• Endosymbiotic: diatoms, , , lichens, fur, bryophytes, gymnosperms, angiosperms • Layered calcareous mounds that contain of cyanobacteria that 21 look like 22

Stromatolites • Stromatolites are produced by successive deposition through “grain trapping” or calcification: • Mucilaginous sheath of cyanos physically blocks the Many are able to fix nitrogen = convert atmospheric N2 (N N) to a usable form (Ammonium: NH +) using movement coarse gain sediments and laminates it to 4 the surface of the N can be limiting; necessary for the production of amino acids • Attract and bind Ca to negatively charged sites

•Locations :hypersaline (Shark Bay,western Aus.), frozen lakes (Antarctic), hot springs (Yellowstone), the Only cyanobacteria and proteobacteria can fix N;

Caribbean BUT cyanobacteria also produce O2 during photosynthesis •Most cyano’s active during the day= layers count the This is a trick, because O inactivates nitrogenase numbers of days 2 •Also they grow up toward the sun and are directional How do they do it??? toward the sun (=can document annual motion of sun) 23 24

6 1. Spatial separation of functions: 2. Temporal separation of functions:

Heterocyst = special cells for N fixation. • Fix N in the dark, Ps in the daytime; • Thick-walled, and larger than other vegetative cells; Every N-fixing cyanobacteria fits into these two hollow looking categories except: = marine, colonial species; fix nitrogen • Not capable of dividing under aerobic conditions in the light through division of labor among cells within a filament (no heterocysts)! • Not photosynthetic, so no

CO2 fixation or O2 production

• Microplasmedesmata connect to other cells in filament

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Domain Bacteria- unicellular, lacking a nucleus, ribosomes, tRNA, The dark side of cyanobacteria? peptidoglycan in the cell wall

Phylum Cyanobacteria- 4484 species Cyanobacterial blooms = and destruction Class Cyanophyceae- 4484 species, 10 orders

Swimmer’s itch = Lyngbia  seaweed dermatitus Order Spirulinales- 57 species filamentous, no specialized structures : released by leads to death in , , & fish Order –1,290 species neurotoxins (e.g. , Oscillatoria) filamentous, no specialized structures hepatotoxins (e.g. , )

Order - 1,365 species filamentous, specialized structures, may have true branching

Oscillatoria 27 28

7 Order Spirulinales Domain Bacteria- unicellular, lacking a nucleus, ribosomes, tRNA, peptoglycan in the cell wall Spirulina • Filament is spiral •Major source for flamingos Phylum Cyanobacteria- blue green algae, origin of the chloroplast • Commercial food source • No heterocysts or akinetes Class Cyanophyceae- • benthic or plantonic, freshwater, thermal & springs, coastal & brackish waters Order Spirulinales- filamentous, no specialized structures • 52 species

Order Oscillatoriales -filamentous, no specialized structures

Order Nostocales- filamentous, specialized structures, may have true branching

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Order Oscillatoriales Order Oscillatoriales - Unbranched filaments GenusTrichodesmium -No readily identifiable sheath, but is present Genus Oscillatoria -No specialized cells - Important marine N fixer -Fix nitrogen - Segregates N fixing within colonies -Early precambrian stromatolites (lacks heterocysts) -Planktonic, form mats on mud, stone, sand, in - More Phycoerythrin than Phycocyanin freshwater, brachish, marine  Red color, gave the Red its name -137 species - Strictly planktonic- marine & -10 species

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8 Domain Bacteria- unicellular, lacking a nucleus, ribosomes, tRNA, Order Nostocales peptoglycan in the cell wall

Phylum Cyanobacteria- blue green algae, origin of the chloroplast • Fixes nitrogen Genus Nostoc • Has heterocysts in the middle of Class Cyanophyceae- filaments •Akinates midway between heterocysts Order - filamentous, no specialized structures •94 species •Freshwater

Order Oscillatoriales -filamentous, no specialized structures

Order Nostocales- filamentous, specialized structures, may have true branching

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Order Nostocales Order Nostocales • Fixes nitrogen • Has heterocysts, often at the Genus Anabaena Genus base of filaments • Produces neurotoxins that become release • Filaments taper at ends when they are ingested by animals • Periphytic on algae, aquatic plants, • Fixes nitrogen stone, wood, high intertidal • Has heterocysts in the middle of filaments •132 species • Akinates adjacent to heterocysts • Planktonic, or periphytic, benthic, soils, • 117 species

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9 Order Nostocales Order Nostocales • Fixes nitrogen GenusTolypothrix •Has heterocysts Genus • Exhibits false branching • 60 species • Produces neurotoxins that are •Mainly submerged, also aerophytic released when they are ingested. habitats • Fixes nitrogen • Has heterocyst at the base of large akinetes •Periphytic or soils •49 species

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Order Nostocales - Has heterocysts Cyanobacteria Cellular Structure: Genus Stigonema - Exhibits True Branching •Nucleus? - Often found as phycobiont in lichens, terrestrial & , freshwater - 62 species •Chloroplasts?

• Pigments?

• Carbon storage?

• Flagella?

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