Evolutionary History
of Biological Diversity
AP Biology
Mrs. Ramon
The Protists
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The Kingdom Protista
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What is a Protist?
Any species that is NOT a plant, animal, fungus or
prokaryote
 Includes over 200,000 species
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Evolution of Protists
“The very first” eukaryotic organisms
 Appeared nearly 1.5 billion years ago
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Classification of Protists
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How they obtain food
Protists
Concept Map
Section 20-1
Protists
are classified by
Animallike
Plantlike
which
which
which
Take in food from
the environment
Produce food by
photosynthesis
Obtain food by
external digestion
Go to
Section:
Funguslike
which include
Decomposers
Parasites
Protists

Animallike Protists: Protozoans

Zooflagellates

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Sarcodines

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Pseudopods for movement and feeding
Amoebas and Foraminferans
Ciliates

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Swim with flagella/flagellum
Absorb food through cell membrane
Use cilia for feeding and movement
Paramecium
Sporozoans

Parasitic and do not move on their own
Protists

Animallike Protists: Protozoans
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Disease

Malaria
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African Sleeping Sickness
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Figure 20-7
Plasmodium carried by the female Anopheles mosquito
Symptoms include chills and fever and can cause death
Zooflagellates of the genus Trypanosomas are responsible for
African sleeping sickness
Trypanosomas are carried by the the tsete fly
Symptoms include chills, rashes and nerve damage leading to
unconsciousness, coma and death
Amebic Dysentery

Severe diarhea and bleeding
Protists

Plantlike Protists: Unicellular Algae

Euglenophytes

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Dinoflagellates (Pyrrophyta)

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Half are photosynthetic half are heterotrophs
Two flagella, some are luminescent
Red tide
Chrysophytes
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Photosynthetic, have flagella but no cell wall (pellicle)
Eyespot
Contain gold-colored chloroplasts
Diatoms

Thin cell walls of silicon (found in glass)
Protists

Plantlike Protists: Red, Brown and Green Algae

Red Algae
Actually includes green, purple or reddish black algae
 Live at great depths
 Found from polar regions to tropics
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Brown Algae
Fucoxanthin gives brown algae its color
 Giant kelp

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Green Algae

Unicellular, colonial or multicellular
Protists

Funguslike Protists

Absorptive heterotrophs, lack cell walls found in
fungi
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Slime Molds
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Cellular slime molds
Acellular slime molds
Water Molds
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Thrive on dead, decaying matter in water and are plant parasites
on land
Irish Potato Famine of 1845