1. Chapter 23: Protistans

3. dinoflagellates charophytes green algae red algae Stramenopiles brown algae chrysophytes oomycotes slime molds parabsalids (e.g., Trichomonas) diplomonads (e.g., Giardia) endosymbiotic origins from prokarytic ancestors protists amoeboid protozoans branch leading to fungi branch leading to animals Alveolates ciliates apicomplexans euglenoids kinetoplastids (e.g., Trypanosoma) “crown” of eukaryotes (rapid divergence) branch leading to plants Fig. 20-2, p.316

4. I. Traditional Protista Organization A. Fungi-like protists: Molds B. Animal-like protists: Protozoans a. Amoeboids b. Ciliates c. Flagellated Protozoans C. Plant-like Protists: Algae a. Dinoflaggelates b. Red Algae c. Brown Algae e. Green Algae

5. II. More Recent Organization A.Flagellated Protozoans (animal-like protists with flagella) 1. Human importance: Giardia, African Sleeping Sickness, Chargas Disease. 2. Example: Euglenoids, such as euglena. Single cell, free-living organism. About 30% are autotrophic. Contain contractile vacuole.

6. Fig. 23.15, p. 383 pelliclemitochondrion Golgi body ER nucleus eyespot shielding a light-sensitive receptor long flagellum contractile vacuolechloroplast Euglena: ‘Plant-like’ ? Some are photosynthetic, other heterotrophs. No cell wall but flexible cell coat. Motile and eukarytoic.

7. II. More Recent Organization 3. Variety in Euglena due to primary endosymbiosis (engulf bacteria).

8. II. More Recent Organization B.Alveolates: Broad group with small sacs under their plasma membrane. 1. Ciliates: Move with cilia (many small extensions). Example: Paramecium. Most are heterotrophs.

9. Fig. 23.6b-d, p. 378 food vacuole food residues being ejected gulletcilia trichocysts (“harpoons”) contractile vacuole filled micronucleus macronucleus contractile vacuole emptied pellicle cillium intact trichocyst basal body of cilium

10. Fig. 20-6b, p.318

11. II. More Recent Organization B. Alveolates: Broad group with small sacs under their plasma membrane. 2. Dinoflagellates: ‘Algae’ and/or predators. a. Algae inside corals. b. Red tide algae (video clip).

12. Fig. 20-9b, p.319

13. II. More Recent Organization B. Alveolates: 3. Malaria: Caused by Plasmodium. Sporozite (liver), Merozoites (liver and blood), gametes (blood, passed to mosquitoes)

14. Fig. 23.14, p. 382 sporozites 3 Sporozites reproduce asexually in liver cells. merozoite 4 Progeny (merozoites) enter bloodstream, invade red blood cells, and reproduce asexually. They may do so many times over a prolonged period. Disease symptoms (fever, chills, shaking) become more and more severe. 5 Some merozoites return to liver and are basis for more episodes of malaria. 6 Other merozoites develop into male and female gametocytes, which are released into bloodstream. male gametocyte in red blood cell sporozoite 2 Mosquito bites a human, sporozoites enter bloodstream and reach liver. 1 In the gut of a female mosquito carrying the malarial parasite Plasmodium, zygotes of the parasite develop into sporozoites, which migrate to her salivary gland. 7 A biting female mosquito sucks blood from infected human. Gametocytes in the blood reach her gut, mature into gametes used in sexual reproduction. Gametes fuse to form zygotes.

15. II. More Recent Organization C. Stramenopiles 1. Some fungi-like organism: potato blights and water molds. 2. Diatoms: algae with silicate shells. 3. Other algae: Golden algae and coccolithophores. 4. Brown Algae: Include Kelp.

16. Fig. 20-12, p.321

17. Fig. 20-13b, p.321

18. holdfast bladder blade stipe Fig. 20-13c, p.321

19. II. More Recent Organization D. Green Algae 1. Many biologist consider these plants, use similar photosynthesis pigments, cell wall w/ cellulose, make starch… 2. Chlorophyta: largest group

20. Fig. 20-16c, p.323

21. Fig. 20-16b, p.323

22. II. More Recent Organization E. Red Algae: Often found at depths in saltwater environments.

23. Fig. 23.19, p. 386 sporophyte (2n) germinating spore (n) 10 cm gametophyte (n) female gametes male gametes zygote Meiosis Diploid Stage Haploid Stage Fertilization

24. II. More Recent Organization F. Ameoboids: Move with pseudopods (false foot) and often involve complex cell communication.

25. p.314b

26. Fig. 20-18a, p.325