23: Protists
- Page ID
- 104398
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Most protists are microscopic, unicellular organisms that are abundant in soil, freshwater, brackish, and marine environments. They are also common in the digestive tracts of animals and in the vascular tissues of plants.
Thumbnail: This scanning electron micrograph (SEM) revealed some of the external ultrastructural details displayed by a flagellated Giardia lamblia protozoan parasite. G. lamblia is the organism responsible for causing the diarrheal disease "giardiasis". (Public Domain; CDC / Janice Haney Carr).