CHAPTER 22 - PROTISTS

Protists

Euglenoids

Diatoms

Three General Protist Life Cycles

Flagellated Protozoans Diplomonads Parabasalids Trypanosomes Euglenoids

Giardia and Trichomonas

Diplomonad – Giardia lamblia

Parabasalid – Trichomonas vaginalis

Parabasalid Species in Termite Gut

Photo from John Breznak, Michigan State University. 2001. Retrieved from: http://www.nsf.gov/od/lpa/news/press/01/pr0154.htm

Kinetoplastids - Trypanosomes

Trypanosoma brucei –African Sleeping Sickness

Tsetse fly – Glossina. 2007. http://www.microbiologybytes.com/introduction/Trypano.html

Kinetoplastids - Trypanosomes

Trypanosoma cruzi. Causes Chagas disease. http://hardinmd.lib.uiowa.edu/cdc/chagas4.html

Reduviid insect – “kissing bug.” Science Daily. 2004. http://www.sciencedaily.com/releases/2004/09/040930121239.htm

A Euglenoid: Euglena gracilis

Foraminiferans and Radiolarians

Heterotrophic single cells with chalky or glassy shells live in great numbers in the world’s oceans; cytoplasm extends through many pores

White Cliffs of Dover/Egyptian Pyramids

Chalky remains of foraminiferans and other organisms with calcium-carbonate shells

About.com. 2011. http://ancienthistory.about.com/od/egypt/ig/Ancient-Egypt/Sphinx.htm

The Alveolates Have a layer of sacs just under the

plasma membrane “Alveolus” means sac.

3 Groups: Ciliates Dinoflagellates Apicomplexans

Ciliates: Predator and Prey Didinium

Ciliate Structure: Paramecium

Dinoflagellates

Council - Garcia, Cara Lea. 2002. http://biology.unm.edu/ccouncil/Biology_203/Images/Protists/dino1.gif

Karenia brevis and Algal Blooms

American Society for Microbiology. 2006. http://dev.microbeworld.org/news/articles/images/dinoflagellates.jpg

Bioluminescent Dinoflagellates

Noctiluca scintillans

Apicomplexans Parasitic alveolates Spend part of life cycle inside host cell Named on complex of microtubules at the

apical end that allows them to enter a host cell.

Sometimes called sporozoans Ex. Plasmodium and Toxoplasm gondii

Life Cycle of Plasmodium

Toxoplasmosis gondii

Dubey, J. P. 2006. http://www.parasitology.com.cn/UploadFile/200957135243451.JPG

Stramenopiles Colorless filamentous molds, photosynthetic

single cells, and large seaweeds belong to the stramenopile lineage

Name means “straw-haired” Grouped according to gene sequence

comparisons 3 Groups:

Diatoms Brown Algae Water Molds

Diatoms

Brown Algae

Fucus - bladderwrack

Macrocystis - Giant Kelp

Parasitic Water Molds Filaments of Saprolegnia infect fish in

aquaria

Phytopthora: The Plant Destroyers

Dead and dying trees near Big Sur, CA, where P. ramorum is epidemic.

Green Algae - Chlorophyte Algae

Volvox

Ulva – “Sea Lettuce”

Codium fragilis – “Dead Man’s Fingers”

Green Algae - Charophyte Algae

Spirogyra. http://silicasecchidisk.conncoll.edu/LucidKeys/Carolina_Key/html/Spirogyra_Main.html

Desmids

Stoneworts (Chara)

Red Alga Antithamnion plumula

Amoeba and Plasmodial Slime Mold

Amoeba proteus Physarum plasmodium

Cellular Slime Mold Life Cycle: Dictyostelium discoideum

Choanoflagellates

Science Notes. 2008. New York Times. http://sciencenotes.wordpress.com/2008/03/06/choanoflagellates-to-sponges-to-metazoa/

Carroll, Sean B. 2010. http://www.nytimes.com/2010/12/14/science/14creatures.html?_r=1

Devitt, Terry. 2001. University of Wisconsin-Madison News. http://www.news.wisc.edu/6920

The End