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Home , Auxospore, Chromista, Coccolithophore

Groups () Dinophyta, Haptophyta, & Bacillariophyta 1.Bacteria- (blue green ) 2.Archae 3. 1. - ,

Chromista 2. - ,

3. - unicellular amoeboids

4. Excavates- unicellular

5. Plantae- rhodophyta, , seagrasses

6. Amoebozoans- slimemolds

7. Fungi- with extracellular digestion

8. - unicellular

Phytoplankton 1 9. Animals- multicellular heterotrophs 2

DOMAIN Eukaryotes Domain Eukaryotes – have a nucei Supergroup Chromista- derived from Chromista = 21,556 spp. chloroplasts derived from red algae Division Haptophyta- 626 spp. coccolithophore contains Alveolates & Stramenopiles according to Algaebase

Group Alveolates- unicellular, plasma membrane supported by flattened vesicles Division Haptophyta- 626 spp. coccolithophore Division Dinophyta- 3,310 spp. of dinoflagellates

Group Stramenopiles- two unequal flagella, chloroplasts 4 membranes

Division Ochrophyta- 3,763spp. Division Bacillariophyta -13,437 spp diatoms

sphere of stone 3 4

1 Division Haptophyta: Coccolithophore Division Haptophyta: Coccolithophore

• Pigments? Chl a &c Autotrophic, Phagotrophic & Osmotrophic Carotenoids:B-carotene, diatoxanthin, diadinoxanthin (uptake of nutrients by osmosis) •Carbon Storage? Sugar: Chrysolaminarian Primary producers in polar, subpolar, temperate & tropical waters

• Chloroplasts? 4 membrane Coccolhliths- external bod y scal es mad e of ca lcium car bonate - keep out bacteria & - predatory defense •Flagella? 2, smooth , equal - focus light into cells & nutrient uptake

• History? Alternation of Generation Haptonema- thread like extension involved in prey capture - Phagotrophic lack and have haptonema 5 6

Haptophyta & Global Biochemistry Division Haptophyta- coccolithophore Genera: Emiliania •Carbon & sulfer cyclingglobal climate •Smallest unicellular •Ubiquitous throughout top 200m • floor limestone accumulation •Tremendous blooms -largest long term sink of inorganic carbon •Armored coating makes the surface more reflective •Cools deeper ocean water •25% of total carbon to deep ocean from coccoliths •Contributes to global warming bc increases the amount of dissolved CO2 in the water

•Produce large amounts of Dimethylsulfide (DMS) & reflect light - Increase acid rain - Enhance cloud formation – sulfate aerosols - Cooling influence on climate

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2 Domain Eukaryotes – have a nuclei Supergroup Chromista- chloroplasts derived from red algae Division Dinophyta: Dinoflagellates Division Dinophyta- 3,310 spp. of dinoflagellates

• Pigments? Chl a & c, carotenoid- B carotene, xanthophyll peridinin gyroxanthin diester •Carbon Storage? Starch

• Chloroplasts? Triple membrane Thylakoids in stacks of 3 whirling flagella • Flagella? 2 unequal flagella Pyrrhos = “fire” - transverse & longitudinal bioluminescent •Life History? Haplontic 9 10

Xanthophyll Peridinin Division Dinophyta - a light harvesting carotenoid - unique in its high ratio of peridinin to chlorophyll 8:2 • Can be heterotrophic (eats food) or autotrophic (makes own food), - makes red tides red or both!

•Obligate heterotrophs- secondary loss of

• Use flagella to capture prey

• All have tri ch ocysts , prot ein ro ds that ca n be ejected, exact function is unknown

•Mucocysts- simple sacs that release mucilage

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3 Dinophyta Life History Dinophyta Morphology Haplontic: 1N thallus, the is the only diploid stage

• Posses two unequal flagella (at right angles to each other) • wall made up of plates (a carbohydrate) • Both flagella are hairy (not mastigonemes)

Normal conditions: Asexual Tranverse undulipodium (flage llum ) Stressful conditions: Fuse with another dinophyta to form hypnozygote (resilient resting stage) Longitudinal undulipodium ()

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Dinophyta Morphology Dinophyta Movement - determined by number & arrangement of thecal plates • Have a slight capacity to move into more favorable areas to increase productivity Apical Pore Thecal Plates • Use flagella to move (Cellulose) Epicone • Longitudinal flagellum  propels in the opposite direction Girdle or Cingulum • Transverse flagellum  this flagella allows for turning and Transverse maneuvering Undulipodium Hypocone

• Some dinoflagellates (<5%) have eyespots that allow detection of Trichocyst Pores light source (mostly fresh water) Sulcul Groove Longitudinal • Trichocysts??? Undulipodium

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4 Spines Dinophyta Genera: Gymnodinium, Noctiluca, • Larger SA/V • Helps to stay suspended in water column • Causes red tides when in high concentrations • Produces , a type of neurotoxin. • Poisons humans who eat shellfish that have been filtering it.

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Dinophyta Bioluminescense Genera: Gymnodinium, Noctiluca, Symbiodinium • Ancient mariners thought “the burning ” were of supernatural origin

• Obligate • The next hypotheses were that the light was emitted from salt •Bioluminescent! molecules or burning phosphorous • Large – up to 2mm • In 1830, scientists agreed it was biological in origin

• Dinophyta are the primary contributors to bioluminescence in the marine habitat

• In bioluminescence, energy from an exergonic (spontaneous; energy released) chemical reaction is transformed into light energy

• Compound responsible is luciferin (term for general class of 19 compounds) which is oxidized and results in the emission of light20

5 Domain Eukaryotes – have a nuclei Supergroup Chromista- chloroplasts derived from red algae Dinophyta Division Bacillariophyta -13,437 spp diatoms Genera: Gymnodinium, Noctiluca, Symbiodinium • zooxanthella • endosymbiont of corals, anemones, foraminiferans and radiolarians • provides host with up to 90% of energy requirements

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Division Bacillariophyta -diatoms Division Bacillariophyta -13,437 spp diatoms • Pigments? Chl a & c carotenoids: fucoxanthin • Most abundant group of marine

•Carbon storage? sugar: laminarin •Sometimes heterotrophic

• Unicellular,,(g) sometimes colonial (chain forming) • Chloroplasts? 4 membranes • Can be planktonic or benthic

• Flagella? Spermatezoids have one flagellum with mastigonemes • Store oil as an energy reserve & help them float at the correct depth

•Life History? Diplontic

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6 Division Bacillariophyta - diatoms Division Bacillariophyta -13,437 spp diatoms

Diatoms often form chains – look filamentous

Centric morphology Pennate morphology25 26

Division Bacillariophyta - Morphology Division Bacillariophyta - Diatoms Movement Frustrules- Two-part boxlike cell walls

•composed of silica (silicon dioxide, SiO2) •silicon can be a limiting nutrient for them •They secrete crystalline structures through Girdle - area of overlap of frustrules holes in the raphe or frustrules

Raphe- central groove •These structures expand in H2O

epitheca •This causes movement in opposite direction theca or frustrule •Movement regulated depending on which girdle (each half) holes they secrete through overlap

hypotheca 27 28

7 Division Bacillariophyta - Reproduction Division Bacillariophyta - Life History •Division rates exceed one per day Diplontic: 2N thallus, the gametes are the only haploid stage •Asexual- individuals get smaller and smaller oogamous

•Sexual- formation of , only way to get bigger 29 30

Domain Eukaryotes – have a nuclei Supergroup Chromista- chloroplasts derived from red algae Division Bacillariophyta -13,437 spp diatoms Genera: • Unicells or in chains Coscinodiscus, , Navicula, Pseudo-Nitzschia • Common in rocky intertidal Coscinodiscus •Common in coastal waters, epiphytic on Pseudo-Nitzschia

• Produces anti-herbivory compound Chaetoceros Domoic Acid • Accumulate in anchovies, eaten by • Spines to slow sinking birds  death and strange behavior • Dense blooms can cause damage to fish gills 31 32

8 Division bacillariophyta-diatoms Dinophyta, Haptophyta, & Bacillariophyta Only phytoplankton with economic value

Petroleum & Natural Gas: •Formed over millions of years from dead diatoms

Diatomaceous earth: •Mine d for filtrat ion purposes , water filters (porous) •Pesticides (plugs up trachea)

33 39 Phytoplankton 34

Primary Production Primary Production • Phytoplankton are the major contributors to primary production in • Phytoplankton are at the base of marine food chains the open ………………………………………………………………..and globally! or webs  primary producers

•Primary Production: the amount of light energy converted to organic compounds by an ecosystems during a given time period

• Chlorophyll a is often measured as a for primary production by phytoplankton

•Important players phytoplankton produce over 99% of • carried out primarily by: •Phytoplankton – open ocean the food supply for marine animals 35 36 •Macroalgae – along the coast

9 Phytoplankton are the base of pelagic food webs Light

• Major factor limiting new cell production

• Limited to growth in the photi c zone – near the sfsurface

• •euphotic zone <200m (good light) •disphotic zone 200-1000m (small but measurable light)

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Light Nutrients •Major factor limiting new cell production (especially N, Fe, Si for diatoms)

•Nutrient Sources: • Rivers, streams, and agriculture (runoff) • • Defecation • Decomposition • fixers

• Compensation depth = depth at which photosynthesis is equal to •Nutrient uptake: respiration (net production = 0) • Advantage of small size • Simple diffusion to supply nutrients and remove wastes • Below this depth = phytoplankton die (can’t grow and deplete reserves) - large SA/V ratio

• Above this depth = phytoplankton grow and are happy 39 7 40

10 Stratification influences: • time spent in the photic zone • nutrient availability (e.g. nutrients sink) Importance of Iron

•The photic zone is often shallower than the upper mixed layer but cells circulating in the • In nitrogen rich waters – what is limiting??? mixed layer are continually + brouggpht into the photic zone •NH4 (Amonium) is utilized directly •Nutrients are generally low in - surface waters and higher at •NO3 (Nitrate) assimilation by nitrate reductase depth requires iron •Pycnocline limits vertical mixing - to the upper regions of lakes and • Algae need iron to utilize Nitrate (NO3 ) as a nitrogen oceans, once cells sink below it source they are lost from the pop.

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“With half a shipload of Fe, Importance of Iron I could give you an ice age”

John Martin’s Hypothesis • 1988 (MLML) Reasoning: • Iron limits phytoplankton • Phyto bloom would take CO production in nutrient rich 2 out of the atmosphere seas •CO2 is a greenhouse gas causinggg global warming

•Iron addition experiment in the Pacific (500 km south of the Galapagos Islands– Mid October 1993 ) – added Fe to 64 sq km

•John died of cancer before he could see the outcome

• Phytoplankton ↑ 85X Satellite picture of a phytoplankton bloom in the Southern • Expt. repeated in the Southern Ocean with similar results Ocean induced by 43 44

11 Ecology

Population Growth of Phytoplankton

Pop growth = rate of new cell production – rate of cell loss (sedimentation/sinking + grazing)

Too much of a good thing (primarily in lakes and nearshore coastal habitats): • Excess nutrients can cause eutrophication, often from runoff •Floating and sinking • Over enrichment of N + P •Grazing • Excessive growth of algae out-competes other organisms, decay of biomass results in anoxia • A big problem in the Baltic 45 46

Adaptations to slow sinking or aid in resuspension Floating and Sinking

• Most phytoplankton are denser than water + tend to sink •Spines to prevent sinking •Some species replace carbohydrates with lipids as a • Stay suspended by water movements and viscous (resistance of fluid storage product (oils = more buoyant) to something moving through it) drag (mechanical force of a solid •Swimming with flagella (phototaxis) moving through a fluid) •Ionic exchange: • Viscous drag slows sinking rates • Move ions in and out of cell to increase or decrease density • Shape: Elongate cells have more SA/V ratio than spherical cells – slow sinking in elongate

• Colonial chain forming arrangements slow sinking

• Water mixing suspends cells

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12 Grazers Grazers Phytoplankton defenses: •Suspension feeding (filter water) o Increase rates of production • Direct feeding o Mucilage sheaths

• May remove size specific individuals o Thick walls

• May remove less resistant Phytoplankton species – o Hard external coverings non-toxic spp o Spines are more for buoyancy but could also protect

• Results in patchy distributions o Form colonies (become too large for some to handle Grazers may also increase Phytoplankton populations o Chemical deterrents (toxic species) – e.g. Paralytic by releasing nutrients through excretion (positive Shellfish Poisoning effect) 49 50

Phytoplankton as indicators of changing environments increase nutrients in water (nitrogen & phosphorous) occur Spring to Fall • Phytoplankton depend upon sunlight, water, and nutrients (April – September in northern hemisphere) 2 million dinoflagellates/liter • Variance in any of these factors over time will affect phytoplankton concentrations 1.blooms are not associated with tides 2.not all algal blooms cause reddish discoloration of water • Phytoplankton respond very rapidly to environmental 3.not all algal blooms are harmful, even those involving red changes discolouration

• Changes in the trends for a given phytoplankton population (i.e. density, distribution, or pop growth rates) will alert scientists that environmental conditions are changing

•Oil companies monitor Haptophyta populations 51 52

13 Harmful Algal Blooms: Seafoam: a complicated biochemical amalgam 1. the production of neurotoxins which cause mass mortalities in fish, seabirds and marine mammals crushed phytoplankton- consist of inorganic and 2. human illness or death via consumption of seafood organic particles of proteins, carbohydrates, and lipids contaminated by toxic algae proteins provide surface tension to allow the bubbles 3. mechanical damage to other organisms, to form such as disruption of epithelial gill tissues in fish, bubbles arise from agitation of the surf resulting in asphyxiation 4.oxygen dep letion of the water column ( hyp oxia or anoxia) from cellular respiration and bacterial degradation

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