Biology 2E: Chapter 23 Protists

Week 6

1. Are protists prokaryotes or eukaryotes?

Protists are eukaryotes.

2. What is the general diversity of protists?
Protists can be:

Unicellular or multicellular

Sexually or asexually reproducing

Autotrophs or heterotrophs

Microscopic or extremely large

3. Are all protists unicellular and microscopic?

No. Most are unicellular, but some are multicellular, and their sizes range from microscopic organisms to extremely large forms such as kelp

4. Can protists be parasitic and cause diseases in humans?

Yes. Some protists are parasites that infect humans and cause disease

5. What are some examples of human diseases caused by parasitic protists?

Trypanosoma can cause African sleeping sickness and Chagas disease.

Giardia lamblia can infect the digestive tract and cause severe diarrhea.

6. Why are photosynthetic protists ecologically important?

They produce oxygen and function as producers in aquatic ecosystems.

7. How can protists form ecologically important symbiotic relationships?

Some live in close relationships with other organisms. For example, photosynthetic protists living in coral tissues help support coral reef ecosystems.

8. What are two major ecological roles of protists from this chapter?

1. Photosynthetic protists serve as producers and produce oxygen.

2. Many protists form symbiotic relationships with other organisms.

9. Why can't protists simply be classified as plants?

Unlike plants, protist gametes and zygotes are not protected from drying out.

10. Why can't protists simply be classified as fungi?

Unlike fungi, protists do not have chitin in their cell walls.

11. Why can't protists simply be classified as animals?

Unlike animals, protists do not undergo embryonic development.

12. Why are protists difficult to classify as a group?

Protists are extremely diverse and complex and cannot simply be classified as plants, animals, or fungi.

13. What does the term "algae" generally refer to?

Protists that perform photosynthesis.

14. What are the three structures/methods protists use for movement?

Cilia, pseudopodia, and flagella.

15. How do cilia allow a protist to move?

Numerous small, hair-like cilia beat in a coordinated manner to propel the organism.

16. How do pseudopodia allow a protist to move?

The protist extends lobe-like pseudopodia that anchor and pull the organism forward.

17. How does a flagellum allow a protist to move?

A whip-like flagellum propels the organism

18. A protist performs photosynthesis and serves as a producer in an aquatic ecosystem. What general term could be used to describe it?

Algae

19. A protist uses hundreds of small, hair-like structures to propel itself. What structure does it use?

Cilia

20. A protist forms temporary lobe-like extensions of its cell to move. What does it use?

Pseudopodia

21. A protist propels itself using a whip-like structure. What does it use?

A flagellum