Name
Protist Classification
Worksheet 16-3
Lesson Objectives
Explain what a “protist” is.
Describe how protists are related to other eukaryotes.
Lesson Summary
The First Eukaryotes Protists are eukaryotes that are not members of the plant, animal, or fungi
kingdoms. The first eukaryotes were protists.
Most protists are unicellular.
Protists are a very diverse group of species.
Many species of protists are more closely related to plants, fungi, or animals than they are to other
protists. Because of this, some scientists think the members of the kingdom Protista should be
reclassified.
Protists—Ancestors and Descendants All eukaryotes are descended from early protists, but
modern protists are very different from their ancestors. Like other eukaryotes, they have been evolving
over the last 2.5 billion years.
The First Eukaryotes
1. What is a protist?
2. Why are brown algae considered protists even though they are multicellular?
3. Why do scientists no longer use the categories of animal-like, plantlike, and fungus like protists to
classify protists?
For Questions 4–7, complete each statement by writing the correct word or words.
4. Most single-celled eukaryotes are currently classified as .
5. Genetic analyses of protists indicate that they belong in six different .
6. Protists were the first .
7. Unlike most protists, which are unicellular, kelp has tissues.
