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COMMON EXAMPLES:Amoeba, paramecium, euglena, volvox, plasmodium

EUKARYOTICHave a nuclear membrane

VERY DIVERSE GROUPmost are unicellular, microscopic, aerobicSome are autotrophic, heterotrophic, sexual, asexual

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ENDOSYMBIONT THEORYEarly eukaryotes developed symbiotic relationships with prokaryotic cells

Prokaryotic cells lived inside eukaryotic cells

Over time, the smaller prokaryotic cells evolved with the eukaryotic cells to become mitochondria and chloroplasts

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EXCRETION AND OSMOREGULATION

Water balance = osmoregulation

Done by contractile vacuole

Wastes removed by diffusion

RESPIRATIONCarbon dioxide and oxygen diffuse in and out

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REPRODUCTIONAsexual

Mitosis and cytokinesis

Budding – similar to mitosis except daughter cell is smaller than parent

Schizogony – nucleus divides many times and cytoplasm divides to form many daughter cells as there are nuclei

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SEXUALLYMeiosis – special nuclear division to reduce chromosome number to haploid

Union of gametes = diploid zygote

Syngamy – fertilization between two individuals

Autogamy – two gametes fuse within one organism

Parthenogenesis – development of organism from gamete without fertilization

Conjugation – exchange of nuclear material between two individuals

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DOMAIN EUKARYOTA

KINGDOM PROTISTA

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ANIMAL LIKE PROTISTS = PROTOZOA

Classified by method of movement

PLANT LIKE PROTISTS = ALGAE

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PROTIST CLASSFICATIONSeparated by feeding habits (nutrition)

AutotrophicAble to make own food

Photosynthetic – 30-40% of all photosynthesis worldwide is done by algae

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PROTOZOAHeterotrophic

Unicellular

4 groups

Sarcodinians

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PHYLUM SARCODINAAquatic, clear cytoplasm, irregular shape

Move by extending lobes of their cytoplasm

Pseudopods (false feet)

Plasmolemma – elastic cell membrane

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LABEL THIS AMEOBA

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PHYLUM ZOOMASTIGINAOften called flagellates because they move using flagella

Absorb food by diffusion through cell membrane

Live off of dead or decaying organic matter or some are parasites

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PHYLUM CILIOPHORACiliates – found in fresh and salt water; usually free-living, most are larger than other protozoaPellicle, cilia, ectoplasm, endoplasm, food vacuole, contractile vacuoleMicronucleus (exchanged during conjugation)Macronucleus (controls daily functions)

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TRICHOCYSTS – spindle shaped alternating between bases of cilia; used as anchor and to paralyze preyOral groove – shallow furrow on one side of cell used to gather foodLocomotion – cilia; avoiding reaction contact with unfavorable conditions and will move away

Reacts to contact, temperature, gravity, water currents, electric currents, acidity and other chemicals

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ReproductionMitosis every 6-12 hours

Conjugation – become sticky and adhere to each other at oral groove and exchange nuclear material

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PHYLUM SPOROZOAMembers cannot move

Reproduce by producing spores

All endoparasites

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PLANT LIKE PROTISTSMost perform photosynthesis

Contain chlorophyll in chloroplast and possibly other pigments

Divided into groups by pigment color

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PHYLUM EUGLENOPHYTAUsually free-living (not a parasite)

Pellicle – covering membrane; maintains shape

Ectoplasm, endoplasm

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Movement toward light using flagella; flagella pulls cell; euglenoid movement expansion and contractions of entire cell

Nutrition – can capture food; can absorb nutrients from water or carry on photosynthesis

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PHYLUM CHLOROPHYTA - GREEN ALGAE

Contain chlorophyll b is their main type (which is very similar to land plants)

Some reproduce sexually

Examples: desmids, spirogyra

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PHYLUM HETEROKONTOPHYTARed algae, brown algae, golden algae

RED ALGAEGrow in warm salt water habitats – toward surface or deep water

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BROWN ALGAEMulticellular and live in cool salt water habitats

Includes giant kelps

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Used to make a variety of products

As a thickening agent in puddings, ice cream

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GOLDEN ALGAE –Some species are colorless, but the vast majority are photosynthetic.

particularly important in lakes, where they may be the primary source of food for zooplankton.

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PHYLUM DINOFLAGELLATA (termed Pyrrophyta in your book)

Nearly all have flagella

Most grow in salt water

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DINOFLAGELLATE

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Cause the red tide

Several microscopic marine algae are notoriously poisonous to hapless humans who consume them in shellfish.

some species are poisonous to animals which feed upon them directly or indirectly.

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FUNGUS-LIKE PROTISTS (MOLDS)CHARACTERISTICS

MOST ARE SMALL AND LIVE IN DAMP PLACES

PROTISTS THAT ACT AS DECOMPOSERS ARE CALLED MOLDS

DIVIDED INTO 3 GROUPS

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PLASMODIAL SLIME MOLDSCan weigh as much as 50 grams and be as large as a human hand (one cell!)

Single cell with many nuclei

Myxomycota - plasmodium

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CELLULAR SLIME MOLDSALTERNATES BETWEEN A SPORE PRODUCING FRUITING BODY FORM AND AN AMEBALIKE FEEDING FORM

The phyla of slime molds:

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WATER MOLDSDECOMPOSERS IN FRESHWATER ECOSYSTEMS

SOME ARE

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IMPORTANCE OF PROTISTSECOLOGICAL ROLES

Provide an essential food base in aquatic food chains