Kingdom Protista

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Protists most diverse kingdom all eukaryotic mostly unicellular aquatic organisms asexual reproduction generally by binary

fission

3 different groups1. plant-like2. animal-like3. fungi-like

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1. Plant-like Protists: Algae all autotrophs contain chlorophyll have cell walls 2 major groups

a) unicellular algae b)multicellular algae

phytoplankton seaweeddiatoms

brown algae

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Plant-like Protists: Algaea) unicellular algae

very important because:1. begin every aquatic food chain2. produce 67% of atmospheric O2

3. overpopulation causes algal blooms which can cause: i) dead algae decomposed by saprophytes consume large amounts of O2 – none left for

fish swamp producedii) produce toxins which kill fish can also be harmful to humans ex. red tide

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Plant-like Protists:Seaweedb) multicellular algae

(seaweed) no real tissues i.e. colonies food source for fish and

humans cell walls of red algae used to

make: i. agarii. gel capsiii. cosmetics

Volvox

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2.Fungus-like Protists (Slime Moulds)

multicellular body (like giant amoeba) called a plasmodium

roll over forest floor feeding on dead organic matter

move very slowly (few mm/day)

reproduce asexually with spores (like fungi) in fruiting bodies

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3. Animal-like Protists all heterotrophs classified by how they move

a) pseudopods: move with cytoplasmic projections called

pseudopods (false feet)

ex. amoeba• some pathogenic•i.e. amoebic dysentery

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Animal-like Protistsb) flagellates

move with long whip-like flagella

some parasitic pathogensex. African sleeping sickness

trypanosome

Giardia lamblia

(beaver fever)

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Animal-like Protistsc) ciliates

move with cilia (short hair-like projections) that can cover cell

ex. paramecium

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Animal-like Protistsd) sporozoa reproduce by asexually

by spores have no means of

locomotion many parasites, which

depend on host body fluids to move

ex. Malaria

anopheles mosquito

RBC

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Paramecium Structure

cilia

contractile vacuolecytoplasmmicronucleusmacronucleus

oral groove

gulletfood vacuole forming

anal pore

food vacuole

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Paramecium

spiral movement

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Paramecium ReproductionBinary fission

(asexual reproduction)

Conjugation (sexual reproduction)

•have two nuclei•exchange micronucleus

withanother paramecium2 new organisms

(genetically identically )

same 2 organisms (genetically different )

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Amoeba Structure

nucleus

ectoplasm

endoplasm

contractile vacuolefood vacuole

pseudopod

cytoplasm

Note: contractile vacuole

•collects all the H2O that diffuses in by osmosis

•contracts & pumps H2O out to stop amoeba from bursting

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Amoeba Feeding

phagocytosis

food

pseudopodpseudopod surrounds

food

food enters a food

vacuole

enzymes break down

food in vacuole

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Amoeba Reproduction

Binary Fission (asexual)

one amoeba divides into 2 identical amoebas