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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 PROTISTAAny eukaryote that is not classified as a fungus, plant, or animal is a PROTIST

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ANIMAL LIKE PROTISTS = PROTOZOA

Classified by method of movement

PLANT LIKE PROTISTS = ALGAEClassified by pigment color

FUNGUS LIKE PROTISTS = MOLDSClassified by body form

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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

HeterotrophicMust eat other material

Unicellular

May be predators, decomposers, or parasites

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PROTOZOAHeterotrophic

Unicellular

4 groups

Sarcodinians

Zooflagellates

Ciliophorans

Sporozoans

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PHYLUM SARCODINAAquatic, clear cytoplasm, irregular shape

Move by extending lobes of their cytoplasm

Pseudopods (false feet)

Plasmolemma – elastic cell membrane

Cytoplasm is divided into ectoplasm and endoplasm

Nucleus, contractile vacuole, food vacuole

Example: Amoeba proteus

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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

Trichonympha lives in the gut of termites (helps termite digest wood)

Trypanosoma – parasite of humans in Africa

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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

Example = paramecium

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PHYLUM SPOROZOAMembers cannot moveReproduce by producing sporesAll endoparasitesHave apical complexes (structures that aid in penetration of host cells or tissues)Example: Plasmodium – causes malaria; carried by vector (female Anopheles mosquito)

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PLANT LIKE PROTISTSMost perform photosynthesis

Contain chlorophyll in chloroplast and possibly other pigments

Divided into groups by pigment colorPHYLUM EUGLENOPHYTA

PHYLUM DINOFLAGELLATA

PHYLUM HETEROKONTOPHYTA

PHYLUM CHLOROPHYTA

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PHYLUM EUGLENOPHYTAUsually free-living (not a parasite)Pellicle – covering membrane; maintains shapeEctoplasm, endoplasmCell mouth, gullet, reservoir (holds flagella), contractile vacuole, food vacuoleStigma (eyespot) - light sensitiveNucleus, chloroplasts

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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

Reproduction – mitosis; form cyst during harsh times

Example: euglena; volvox

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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

Most live in fresh water or moist soil

Many live in symbiotic relationshipsLichen – organism composed of an algae and a fungi living together as one

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PHYLUM HETEROKONTOPHYTARed algae, brown algae, golden algae

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

Perform photosynthesis

Example: Red moss

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BROWN ALGAEMulticellular and live in cool salt water habitats

Includes giant kelps

Have an alternation of generations life cycle (means that part of life is spent reproducing asexually and part is spent reproducing sexually)

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Used to make a variety of productsAs a thickening agent in puddings, ice creamUsed as food for animals (processed)

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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.

not considered truly autotrophic because nearly all become heterotrophic in the absence of adequate light, or in the presence of plentiful dissolved food.

EXAMPLES - DIATOMS

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PHYLUM DINOFLAGELLATA (termed Pyrrophyta in your book)

Nearly all have flagella

Most grow in salt water

Most are free-living (meaning they are not parasites); some have symbiotic relationships with other organisms

When agitated undergo reaction that produces light bioluminescent

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DINOFLAGELLATE

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Cause the red tideSeveral 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. Some of the toxins these species produce are seriously toxic. Often, the algae themselves are unaffected, as are the filter feeders, especially shellfish, for whom micro-algae are the principal diet. However, to carnivores further up the food chain, including humans, these toxins are potentially FATAL.

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FUNGUS-LIKE PROTISTS (MOLDS)CHARACTERISTICS

MOST ARE SMALL AND LIVE IN DAMP PLACESPROTISTS THAT ACT AS DECOMPOSERS ARE CALLED MOLDS

DIVIDED INTO 3 GROUPSPLASMODIAL SLIME MOLDSCELLULAR SLIME MOLDSWATER MOLDS

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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

In unfavorable conditions

Moves somewhere else

Creates a fruiting body

Myxomycota - plasmodium

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

SINGLE CELLS UNITE TO FORM ONE LARGE MASS (PSEUDOPLASMODIUM) WHEN TIMES ARE HARSH

The phyla of slime molds:

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WATER MOLDSDECOMPOSERS IN FRESHWATER ECOSYSTEMS

SOME ARE PARASITIC

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IMPORTANCE OF PROTISTSECOLOGICAL ROLES

Provide an essential food base in aquatic food chains

Carry out more than 30-40% of Earth’s photosynthesis

Protozoans help keep the number of bacteria in check