Protists

Definition

Protists are a diverse group of unicellular eukaryotic microorganisms that can be free-living or parasitic. They inhabit various environments and exhibit a range of nutritional and reproductive strategies.

5 Must Know Facts For Your Next Test

1. Protists are classified into three main groups: protozoa, algae, and slime molds based on their characteristics.
2. Many protists are capable of both sexual and asexual reproduction, allowing them to adapt quickly to environmental changes.
3. Protozoa such as Plasmodium and Trypanosoma are significant human pathogens causing diseases like malaria and sleeping sickness respectively.
4. Protists often form cysts to survive in harsh conditions, ensuring their survival until they reach a favorable environment.
5. Some protists have complex life cycles involving multiple hosts or stages, which can complicate treatment and control measures.

Review Questions

• What are the three main groups of protists?
• Name two diseases caused by pathogenic protozoa and identify the causative agents.
• Why do some protists form cysts, and what advantages does this provide?

Related terms

Eukaryote: An organism whose cells contain a nucleus surrounded by a membrane.

Pathogen: A microorganism that causes disease in its host.

Cyst: A dormant form of some microorganisms that allows them to survive unfavorable conditions.