Diversity of Protists: The Endosymbiotic Theory Explained!

1. KEY CONCEPT Kingdom Protista is the most diverse of all the kingdoms.

2. Protists are eukaryotes that are not animals, plants, or fungi. Have a nucleus and other membrane-bound organelles Protists can be animal-like, plantlike, or funguslike.

3. Animal-like protists consume other organisms. • heterotrophs • single-celled

4. Plantlike protists are photosynthetic. • single-celled, colonial, or multicellular • no roots, stems, or leaves

5. Funguslike protists decompose dead organisms. • heterotrophs • can move, whereas fungi cannot

6. Endosymbiotic Theory-How Eukaryotes came to be- • Scientists think protists were the first eukaryotes to evolve. • Endosymbiosis refers to one species living within another (the host) • Movement of smaller photosynthetic & heterotrophic prokaryotes into larger prokaryotic host cells • Formed cell organelles chloroplast mitochondria

7. Protists are difficult to classify. • Protista is one kingdom in the domain Eukarya.

8. Protist classification will likely change. • Some protists are not closely related. • Molecular evidence supports reclassification.

9. KEY CONCEPTAnimal-like protists are single-celled heterotrophs that can move. They are classified by how they move.

10. macronucleus contractile vacuole food vacuole oral groove micronucleus cilia Animal-like protists move in various ways. • Animal-like protists are often called protozoa.

11. Protozoa with flagella are zooflagellates PHYLUM Zoomastigophora • flagella help zooflagellates swim • more than 2000 zooflagellates

12. Flagellates- move using flagella Free living by absorbing dead or decaying organic matter OR some are parasites EX:Trichonympha lives in the gut of termites (helps termite digest wood) D. PHYLUM ZOOMASTIGOPHORA Trichomonas vaginalis: an STD

13. Zoomastigophora Tsetse Fly: carries Trypanosoma to humans; in other words, it’s a Vector for African Sleeping Sickness American Sleeping Sickness (Chagas disease) – carried by reduviid bug

14. Phylum Zoomastigophora

15. Some protists move with pseudopods. • change shape as they move • amoebas

16. Pseudopods- (“fake feet”) used for feeding and locomotion. • Saltwater and freshwater • Asexual reproduction Food vacuole pseudopods nucleus

18. Some protists move with pseudopods. • change shape as they move • amoebas PHYLUM Rhizopoda • Forams – PHYLUM Foraminifera

19. Cliffs of Dover

20. Some protozoa move with cilia PHYLUM Ciliophora. macronucleus contractile vacuole food vacuole oral groove micronucleus cilia • cilia help protists swim and capture food • more than 8000 ciliates

21. Ciliates – Use Cilia for movement. found in fresh and salt water Draw and label p.543 A. PHYLUM CILIOPHORA

22. Phylum Cilophora paramecium

23. Phylum Cilophora

24. TWO KINDS OF NUCLEI: Macronucleus – controls daily functions such as feeding, eliminating waste, and maintaining water balance Micronucleus – used for reproduction Phylum Ciliophora

25. Reproduce Asexually, but maintain genetic variation through Conjugation: exchange genetic info Phylum Ciliophora

26. Phylum Apicomplexa • Protists that do not move. • Form sporozoites • Ex. Plasmosdium

27. C. PHYLUM APICOMPLEXA • Sporozoans- Form spores at some point in their life cycle. • Lack locomotion • Sexual and Asexual reproduction • Intestinal parasites Plasmodium (Malaria) It’s Vector: Anopheles Mosquito

28. human liver sporozoites liver cells developed parasites red blood cells Some animal-like protists cause disease. • Malaria is caused by Plasmodium and spread by mosquitoes. • Sleeping sickness is caused by Trypanosoma and spread by Tsetseflies. • American Sleeping Sickness (Chagas disease) – carried by reduviid bug • A giardia infection is caused by Giardia and spread through water. Malaria Infection

29. KEY CONCEPTAlgae are plantlike protists.

30. colony daughter colony Plantlike protists can be single-celled or multicellular. • Photosynthetic plantlike protists are called algae. • Most perform photosynthesis • Contain chlorophyll (green pigment) and possibly secondary pigments • Classified by their pigment color

31. pellicle contractile vacuole nucleus flagellum chloroplast eye spot • Phylum Euglenophyta • mostly photosynthetic • some heterotrophic • single-celled • one or two flagella • some animal like traits • Euglenoids are a large group of plantlike protists.

32. Have an “eye spot” that is sensitive to light. Euglenoids

33. Phylum Dinoflagellata - Dinoflagellates are mostly marine plantlike protists. • have two flagella • may be bioluminescent • have stiff protective plates • can cause red tide • Produce a lethal nerve toxin Dinoflagellates

34. DINOFLAGELLATES • Phyla of Algae • Dinoflagellates- “The spinning ones” • 2 flagella at right angles to each other, causes it to spin as it moves. • Mostly found in saltwater. • Can be bioluminescent: Glow

35. Dinoflagellates • ALGAL BLOOMS: • In good conditions, will reproduce in GREAT numbers. • Clog fish gills • Die, decompose, and deplete the oxygen supply, suffocating marine life.

36. Diatoms are plantlike protists with glasslike shells. • shells made of silica (glass) • produce large amounts of oxygen • Phylum Bacillariophyta

37. Phyla of Algae Diatoms- “The Golden Boxes” Made of chlorophyll (green) & carotenoids (golden-yellow) Reproduction- sexual and asexual. Cell wall- made of hard silica (glass) A. DIATOMS

38. Diatoms • Made of 2 halves: The smaller half fits inside the bigger half, like a box and lid. • Store their food as oil, so they float at the top of the water where they can get sunlight for photosynthesis.

39. Yellow/green algae contain carotenoids • Green algae contain chlorophyll a and b. • Brown algae contain chlorophyll c. • Multicellular algae are classified by their pigments. • Red algae contain chlorophyll a and phycoerythrin.

40. D. Phylum Chrysophyta • Chrysophytes- “The Colonists” • Yellow-Brown secondary pigments (carotenoids) • Form colonies- a group of cells that live in close association.

41. E. Brown Algae • Phylum Phaeophyta • Brown algae- “The Brown Ones” • Fucoxanthin pigments • Multicellular • Largest algae Ex: Giant Kelp can grow up to 30-60 cm a day.

42. Used to make a variety of products As a thickening agent in puddings, ice cream Used as food for animals (processed) Ex. Giant Kelp Brown Algae

43. Brown Algae

44. F. GREEN ALGAE • Phylum Chlorophyta • Green algae- “The Green Ones” • Mostly freshwater • Very similar to plant cell walls • Chloroplasts w/ chlorophyll pigments

45. Green Algae • Scientists think the first plants may have evolved from green algae.

46. G. RED ALGAE • Phylum Rhodophyta • Red algae- “The Red Ones” • Warm saltwater habitats • Perform photosynthesis • Even at depths of 100 meters! • Red & blue secondary pigments (phycobilins).

47. Red Algae Seaweed

48. Red Algae Example: Red moss

49. Many plantlike protists can reproduce both sexually and asexually. • All algae can reproduce asexually. • Multicellular algae can fragment. • Chlamydomonas divides into zoospores.

50. Some species alternation of generations. • Some algae produce sexually. • Sexual reproduction can be triggered by environmental stress.