Bacteria, Viruses, and ProtistsProtists |
What are some differences in characteristics between some protists? |
The great diversity among protists has made their grouping and classification difficult. Characteristics used to classify protists include mode of locomotion, presence or absence of flagella and cilia, body form and coverings, pigmentation, the ability to conduct photosynthesis, type of nutrition, and whether the organism is unicellular or multicellular. The following list includes one of the many classifications, along with some characteristics of certain protists:
Phylum |
Morphology |
Body form/covering |
Locomotion |
Pigment/photosynthesis |
Rhizopoda |
Single cell |
No definite shape; shells in some |
Pseudopodia (means “false foot”) |
None |
Foraminifera |
Single cell |
Shells |
Cytoplasmic projections |
None |
Actinopoda |
Single cell |
Skeletons |
Pseudopods reinforced with microtubes |
None |
Chlorophyta |
Single cell and colonial multicellular |
Cellulose in cell wall |
Flagella; some species are nonmotile |
Chlorophyll |
Rhodophyta |
Mostly multicellular |
Cellulose |
Nonmotile |
Chlorophyll and phycoerythrin |
Phaeophyta |
Multicellular |
Cellulose |
Flagella |
Chlorophyll |
Chrysophyta |
Single cell; some colonial |
Shells with silica |
No flagella; move by gliding over secreted slime |
Chlorophyll |
Pyrrhophyta |
Single cell; some colonial |
Mostly cellulose plates |
Flagella |
Chlorophyll; carotenoids |
Euglenophyta |
Single cell |
allowing |
Flexible pellicle carotenoids euglenoids to change their shape |
Flagella; Chlorophyll |
Zoomastigophora |
Single cell |
None |
Flagella |
None |
Apicomplexa |
Single cell |
Spores |
Nonmotile |
None |
Ciliophora |
Single cell |
None |
Cilia |
None |
Dictyosteliomycota (or, in part, Acrasiomycota) |
Single cell during most of the life; multicellular during reproductive stages |
Cellulose (spores) |
|
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Myxogastria |
Multinucleate mass of cytoplasm |
None |
May have flagella |
None |
Oomycota |
Coenocytic mycelium |
Cellulose |
Flagella |
None |