ProtistsProtists

The world of Protists:The world of Protists:Animal-like ProtistsAnimal-like ProtistsPlant-like ProtistsPlant-like Protists

Fungus-like ProtistsFungus-like Protists

The The endosymbiotic theoryendosymbiotic theory states that some eukaryotic organelles states that some eukaryotic organelles evolved from prokaryotes. For example, the mitochondrion, evolved from prokaryotes. For example, the mitochondrion, chloroplast, and other plastids originated as prokaryotic cells that chloroplast, and other plastids originated as prokaryotic cells that came to reside within a host cell. They enabled the host cell to use came to reside within a host cell. They enabled the host cell to use sunlight as an energy source (the chloroplast) and use aerobic sunlight as an energy source (the chloroplast) and use aerobic cellular respiration (the mitochondrion). In return, the host cell cellular respiration (the mitochondrion). In return, the host cell provided the necessary nutrients, a stable chemical environment, provided the necessary nutrients, a stable chemical environment, and protection. Evolutionary change eventually resulted in this and protection. Evolutionary change eventually resulted in this relationship being obligate.relationship being obligate.

Below: Heterotrophic prokaryotes that engulfed (or became infected Below: Heterotrophic prokaryotes that engulfed (or became infected by) photosynthetic prokaryotes were able to benefit by using the by) photosynthetic prokaryotes were able to benefit by using the sugars produced using solar energy. The prokaryotes benefited by sugars produced using solar energy. The prokaryotes benefited by receiving necessary nutrients from their host cell. The chloroplast receiving necessary nutrients from their host cell. The chloroplast and other plastids evolved from this photosynthetic endosymbiont.and other plastids evolved from this photosynthetic endosymbiont.

Protist DiversityProtist Diversity200,000 species come in 200,000 species come in

different shapes, sizes, and different shapes, sizes, and colorscolors

All are All are eukaryoteseukaryotes – have a – have a nucleus and membrane-nucleus and membrane-bound organellesbound organelles

ProtozoansProtozoans

Animal-like ProtistsAnimal-like Protists

ProtozoansProtozoansUnicellularUnicellular – made up of one – made up of one

cellcellHeterotrophsHeterotrophs – they eat – they eat

other organisms or dead other organisms or dead organic matterorganic matter

Classified by how they moveClassified by how they move

PhylaPhyla of Protozoans of ProtozoansAmoebasAmoebas

FlagellatesFlagellates

CiliatesCiliates

SporazoansSporazoans

AmoebasAmoebas: the blobs: the blobs

No cell wallNo cell wallMove using Move using pseudopodspseudopods – –

plasma extensionsplasma extensionsEngulf bits of food by Engulf bits of food by

flowing around and over flowing around and over themthem

FlagellatesFlagellates: the : the motorboatsmotorboats

Use a whip-like extension Use a whip-like extension called a called a flagellaflagella to move to move

Some cause diseasesSome cause diseases

Trichomonas foetusTrichomonas foetus : cow disease : cow disease

Trichomonas vaginalis: an STDTrichomonas vaginalis: an STD

CiliatesCiliates: the hairy ones: the hairy onesMove beating tiny hairs Move beating tiny hairs

called called ciliacilia

SporazoansSporazoans: the : the parasiteparasite

Non-motileNon-motile - Do not move - Do not moveLive inside a Live inside a hosthostOne type causes One type causes malariamalaria

Malaria in red blood cellsMalaria in red blood cells

Pneumonia in aids patientsPneumonia in aids patients

AlgaeAlgae

Plantlike ProtistsPlantlike Protists

What are Algae?What are Algae?MulticellularMulticellular – made of more – made of more

than one cellthan one cellPhotosyntheticPhotosynthetic – make their – make their

own foodown foodNo roots, stems, or leavesNo roots, stems, or leavesEach has Each has chlorophyllchlorophyll and other and other

photosynthetic pigmentsphotosynthetic pigments

PhylaPhyla of Algae of AlgaeEuglenoidsEuglenoids

DiatomsDiatomsDinoflagellatesDinoflagellates

Red, Brown, & Green AlgaeRed, Brown, & Green Algae

EuglenoidsEuglenoids: The : The SurvivorsSurvivors

AquaticAquaticMove around like animalsMove around like animalsCan ingest food from Can ingest food from

surroundings when light is surroundings when light is not availablenot available

DiatomsDiatoms: The Golden : The Golden OnesOnes

Have shells made of silica Have shells made of silica (glass)(glass)

Photosynthetic pigment Photosynthetic pigment called called carotenoidscarotenoids – give – give them a golden colorthem a golden color

DinoflagellatesDinoflagellates: The : The Spinning OnesSpinning Ones

Spin around using two flagellaSpin around using two flagellaResponsible for Red TidesResponsible for Red TidesCreate toxins that can kill Create toxins that can kill

animals and sometimes animals and sometimes peoplepeople

Red AlgaeRed Algae: : The…uh…Red Ones The…uh…Red Ones

(duh)(duh)SeaweedsSeaweedsMulticellular, marine Multicellular, marine

organismsorganismsHave red and blue Have red and blue

pigmentspigments

Brown AlgaeBrown Algae: : The Brown Ones The Brown Ones

(You think?)(You think?)

They have They have air bladdersair bladders to to help them float at the surface help them float at the surface – where the light is.– where the light is.

Green AlgaeGreen Algae: : Yeah, You Guessed it, Yeah, You Guessed it,

The Green OnesThe Green OnesMost live in Most live in fresh waterfresh waterCan be unicellular or Can be unicellular or

multicellularmulticellularLive alone or in groups Live alone or in groups

called called coloniescolonies

Fungus-like ProtistsFungus-like Protists

Characteristics in Characteristics in CommonCommon

All form delicate, netlike All form delicate, netlike structures on the surface structures on the surface of their food sourceof their food source

Obtain energy by Obtain energy by decomposing organic decomposing organic materialmaterial

PhylaPhylaofof

Fungus-like ProtistsFungus-like ProtistsPlasmodium Slime MoldsPlasmodium Slime Molds

Cellular Slime MoldsCellular Slime Molds

Water Molds & Downy Water Molds & Downy MildewsMildews

Slime MoldsSlime Molds

Live in cool moist, shady Live in cool moist, shady places where they grow on places where they grow on damp, organic matterdamp, organic matter

Plasmodium Slime Plasmodium Slime MoldsMolds

Form Form plasmodiumplasmodium: a mass : a mass of cytoplasm that contains of cytoplasm that contains many diploid nuclei but no many diploid nuclei but no cell walls or membranes – cell walls or membranes – its feeding stageits feeding stage

Creeps by amoeboid Creeps by amoeboid movement – 2.5 cm/hourmovement – 2.5 cm/hour

Plasmodium Plasmodium continued…continued…

May reach more than a meter May reach more than a meter in diameterin diameter

Form reproductive structures Form reproductive structures when surroundings dry upwhen surroundings dry up

SporesSpores are dispersed by the are dispersed by the wind and grow into new wind and grow into new plasmodiumplasmodium

Cellular Slime MoldsCellular Slime MoldsIn feeding mode, they exist In feeding mode, they exist

as individual amoebic cellsas individual amoebic cellsWhen food becomes When food becomes

scarce, they come together scarce, they come together with thousands of their own with thousands of their own kind to reproducekind to reproduce

May look like a plasmodiumMay look like a plasmodium

Water Molds and Water Molds and Downy MildewsDowny Mildews

Live in water or moist Live in water or moist placesplaces

Feed on dead organisms Feed on dead organisms or parasitize plantsor parasitize plants

Fuzzy white growthsFuzzy white growths

That’s AllThat’s All