
biol1110_kingdom_protista_taxonomy 11/27/06
BIOL 1110 REEDER
KINGDOM PROTISTA TAXONOMY
I. Protozoan Protistans
A. Phylum Sarcodina (ameboids)
1. Move by ameboid movement and engulf (phagocytize) prey with pseudopodia or are
flagellated
2. Sarcodine (Rhizopoda) ameboid freshwater species, Amoeba proteus; also, Entamoeba
histolytica is the causative organism of amoebic dysentery; others can inhabit seawater or
soil
a. Contractile vacuole
b. Marine forms with shells of calcium carbonate or silica
1) Foraminiferans: inhabit warm ocean waters of the world; secretes an elaborate
chalky, calcareous, snail-like (CaCO3) shell with thousands of holes by which long,
thin, threadlike pseudopodia can pass; their remains (shells) sink to the bottom and
form limestone or chalk; the famous white cliffs of Dover in England; oil deposits are
potentially indicated by their fossilized remains.
2) Radiolarians: exclusively marine; have silicious exoskeletons in very intricate forms,
through which extend stiff radiating spines; oldest known group of animal like
organisms; compressed through time into siliceous, sedimentary rock
3) Accumulated shells of both types are a primary component of many ocean sediments
B. Phylum Mastigophora (flagellates): The zoo flagellates are primarily free-living, flagellated,
and have a single central nucleus with some ameboid capability; utilizes phagocytosis, while
others have an oral groove (mouth) or a cytopharynx; pathogenic forms include Trichomonas,
Giardia, Trypanosoma, and Leishmania.
1. Trypanosome group: Trypanosoma: parasite that develops in the salivary glands of the tsetse
fly (vector) and then infects new host by biting (cattle, humans) leading to African sleeping
sickness; parasite then inhabits blood of the host.
2. Trichosome group: worldwide nuisance in humans transferred via sexual intercourse;
primarily parasitizes mucosa of the vagina
3. Giardia : contaminant to the water supply resulting in diarrhea
4. Leishmania: sand fly vector resulting in cutaneous and visceral infection; Gulf War
C. Phylum Ciliophora (ciliates):
1. Compared to other protists, the ciliates are the most complex and highly organized due to
extensive organelle specialization
2. Locomotion by cilia that either is all over the body or is in specialized areas of the cell
surface; cilia around mouth region function for nutrition
3. Pellicle of the body wall and numerous trichocysts: threadlike organelles that can be
discharged to the outside; some have barbed tips, and some eject poison in the following
functions: anchorage, defense, or prey capture.
4. Digestion involves formation of a food vacuole with lysosomes assisting breakdown
5. Contractile vacuole: one located at each end of organism for osmoregulation
6. At least two nuclei:
a. Macronucleus: cell growth and metabolism
b. Micronucleus: sexual reproduction and heredity
7. Examples: Paramecium, Vorticella, Stentor; parasitic Balantidium coli (diarrhea)
D. Phylum Apicomplexa (sporozoans):
1. All members are parasites with complicated life histories found infecting nearly all the major
groups of the animal kingdom; primarily utilize insect vectors and one to two hosts