Protistans
Chapter 23
Instructor Notes
Key Concepts:
The kingdom Protista includes single-celled eukaryotic cells
Fungu- like protistans include some parasitic organisms that are decomposers
Animal-like protistans include nonphotosynthetic flagellated protozoans, sporozoans,
and ciliates
Key Concepts:
Many plant-like protistans are photosynthetic flagellates and are important members of
phytoplankton
Some protistans are multicelled forms that include the red, brown, and green algae
Parasitic and Predatory Molds
Resemble fungi
Chytrids: mycelium - hyphae
Water molds: mycelium - hyphae; Irish Potato Blight
Slime molds: Aggragate slug, move - Fig. 23.3
The Animal - Like Protistans
Protozoans - Groups: Take definitions from table 23.1, pg 376
Sarcodina
Amoebas
Mastigophora
Flagellates
Apicomplexa
Sporozoans
Ciliophora
Ciliates
A Sampling of Ciliated Protozoans
Ciliated protozoans
Paramecium: p378-9. Know structure as shown on Fig. 23.6 b.
Free-living and motile
Cilia
Contractile vacuole
Ciliated Protozoans
Reproduction
Sexually or asexually
Conjugation
Ameoboid Protozoans
Sarcodina
Amoebas
Foraminiferans
Heliozoans
Radiolarians
Movement
Pseudopods
Animal-like Flagellates
Mastigophora
Parasites or free living predators
Flagellated protozoans
Giardia lamblia
Trichomonas vaginalis
Trypanosomes
African Sleeping Sickness
Chagas disease
Representative Sporozoans
Sporozoan
Life cycle complex
Involve 2 hosts or more
Plasmodium
Malaria
Cryptosporidium
Diarrhea
Toxoplasma
Birth defects
Life Cycle of Plasmodium - Malaria
Infected mosquito bites human
Sporozoites enter bloodstream and move to liver
Sprozoites produce merozoites
A Sampling of the Single - Celled Algae
Algae
Euglenoids
Euglena
Chrysophytes
Diatoms
Silica shells
Golden algae
Yellow-green algae
Dinoflagellates
Marine
Heterotrophs
Red tides
Toxin
Mollusks and fish
Massive die-offs
Raw sewage and fertilizer
Euglenoids: Red Algae - Rhodophyta
Red, green, purple or nearly black
Accessory pigments, mainly phycobilins
Most abundant in tropics
Commercial products
Agar
Carrageenan
Nori
Brown Algae- Phaeophyta
Olive-green, golden, or dark brown
Carotenoids and chlorophylls a, c1 , and c2
Giant kelps are largest, most complex protistans
Green Algae - Chlorophyta
Most similar to plants
Chlorophylls a and b
Largest number of species ( > 7,000)
Diverse
Chlamydomonas - single-celled, freshwater
Volvox - colonial, freshwater
Ulva - marine “sea lettuce”
In Conclusion
Protistans are eukaryotes
Many are heterotrophs, including water molds, chytrids, slime molds & protozoans
The fungus-like protists are decomposers or parasites
Animal-like protozoans are internal parasites or live freely in aquatic habitats
In Conclusion
Sporozoans have complex life cycles involving multiple hosts
Single-celled and multiple-celled algae are photoautotrophs
The red, brown and green algae are multicelled photosynthesizers
The protistans are the simplest of the eukaryotes