KINGDOM PROTISTA Chapter 22

1. KINGDOM PROTISTAChapter 22

2. I. Domain Eukarya, Kingdom Protista A. All are Eukaryotes; a very diverse group. B. Are usually unicellular, if multicellular, no tissues are formed C. Reproduce asexually by binary fission and sexually D. Examples 1. Algae 2. Protozoa 3. Slime molds

3. E. The Algae—marine ones produce most of the atmospheric oxygen 1. Characteristics a. All contain chlorophyll, but some also have other color pigments b. Most are aquatic, but some live on land

4. c. Many are unicellular, but some are multicellular and can be hundreds of feet long! d. Some have flagella and can move, but most are free floating e. Important in the aquatic food chain: Sunlight—Producers—Consumers

5. 2. Green Algae—about 7,000 species a. Most like land plants; photosynthetic. b. Have chloroplasts and store sugar as starch c. Fresh water, land, and marine (Ulva or “sea lettuce”) in Galápagos)

6. Marine iguana feeding on Ulva, “sea lettuce”

7. d. Spirogyra (lab) spiral shaped chloroplast e. Volvox (lab)—body plan is a colony of cells f. Chlamydomonas—flagellated haploid cells, common in ponds; in low light the cells form + and – gametes which fuse to form diploid zygote.

8. Spirogyra Chlamydomona Volvox

9. 3. Diatoms a. Fresh water and marine b. Have chlorophyll and golden brown color pigments c. Important O2 producers d. Have silica in cell walls— form “shells” with top and bottom halves

10. Diatoms with a two-part shell containing silica.

11. e. Dead ones fall to the bottom of the ocean and fossilize into diatomaceous earth—many uses (1) added to paint and used on road signs to reflect headlights at night (2) abrasive added to toothpaste, tooth polish

12. (3) additive in animal feed— to kill parasitic worm eggs (4) natural pesticide (5) when heated and crystallized, it is then used in swimming pool filters, but this is dangerous to breathe.

13. 4. Red Algae a. Most are multicellular and live in marine water b. Usually smaller and more delicate than brown algae; up to a meter in length c. Economic significance (1). Source of agar used to make culture medium in microbiology (2). Capsules for vitamins and drugs (3). Dental impression material

14. The red alga Antithamnion plumula

15. 5. Brown Algae a. Multicellular and marine water b. Some of the largest seaweeds (Kelp) (50-100 meters long) c. Anchored by holdfast and buoyed by air bladders-(Rockweed Fucus in lab)

16. Giant Kelp

17. Fucus

18. d. Economic significance (1). Provide food and habitat for marine organisms (2). Also used as human food (3). Used in fertilizer (4). Source of algin used as emulsifier (prevents ice crystals from forming in ice cream, makes marshmallows soft, used to make cream cheese)

19. F. The Protozoans 1. General Characteristics a. Eukaryotes b. Usually unicellular; if multicellular, no tissues c. Discovered by Leeuwenhoek— “wee beasties” d. Most have asexual reproduction (binary fission)—eat, grow, split in half.

20. Leeuwenhoek and his microscope.

21. e. Usually aquatic, but some are terrestrial and some live inside organisms f. Have food vacuoles for food digestion g. Have contractile vacuoles—water pumps, eliminate excess water esp. in fresh water protists that live in hypotonic solutions-swell with water and would burst if didn’t eliminate it. h. Usually motile, often classified by how they move

23. 2. The Flagellates (Phylum Zoomastigorphora) a. Move with one or more whip-like flagella b. Examples (1). Trichonympha collaris lives in gut of termites and digests wood for the termite for itself and the termite— mutualism—symbiosis

24. Trichonympha collaris

25. (2). Giardia lamblia—causes severe diarrhea in humans—contaminates drinking water; can’t drink untreated water in US (3). Trichomonas vaginalis— STD disease

26. Giardia lamblia Damage tointestinal wallfrom suckers.

27. Trichomonas vaginalis

28. (4) Trypanosoma brucei (a). Causes African Sleeping Sickness (b). Insect vector (carrier) tse tse fly— blood sucking insect (c). Parasite lives in blood stream of most wild mammals—no effect on them—have a natural immunity

29. (d). Transmitted in the saliva of the tse tse fly to humans (e). Attacks the nervous system, lethal coma is produced (f). Prevents humans from living in many parts of Africa

30. Trypanosoma brucei which causes African Sleeping Sickness

32. (5). Euglenoids (a). Small, live in freshwater (b). Some have chloroplasts; eyespot helps them detect light; photosynthesize (c). Move with 2 flagella (d). God’s joke on taxonomists—plant or animal?

34. (6). Trypanosoma cruzi— causes Chaga’s disease (a). Kissing bugs bite face, defecate leaving protozoans in feces. (b). Scratching bite introduces parasite into the bite wound.

35. (c). Affects heart and digestive organs. (d). Darwin probably suffered from it—describes being bitten by the host bug in his Voyage of the Beagle when he explored in Tierra del Fuego. (e). Mostly found in Mexico and South America.

36. Vector and Parasite of Chaga’s Disease

37. 3. The Ciliates—estimated 8,000 species a. Move with cilia—numerous, hair— like structures b. Most complex protozoans c. Food moves down a gullet— pinches off into food vacuoles d. Wastes are eliminated through an anal pore

38. e. 2 nuclei—Macronucleus controls most activities of cell; Micronucleus involved with a type of sexual reproduction called conjugation—DNA is exchanged between 2 cells f. Also have asexual reproduction through binary fission g. Examples—Paramecium and Stentor

40. Didinium feeding on a Paramecium

41. 4. Dinoflagellates—have 2 flagella; rotate as it moves a. When waters are warm and nutrients high, so many they cause “red tide” b. Secrete a neurotoxin poison that causes wide-spread fish and shell fish kills

42. c. Toxins cause tingling of face, neck, headache, dizziness, and can paralyze humans who eat shellfish that have fed on dinoflagellates. d. Important food source for small animals in ocean e. Some are endosymbionts of reef coral—algae provide sugars and O2 and the coral gives protection and CO2.

43. Dinoflagellate

44. Red Tide Fish Kill

45. 5. Sporozoans--Apicomomplexans a. Nonmotile parasites of animals form spores at some point in their life cycle

46. b. Examples include (1). Plasmodium vivax (a).Causes one type of malaria (b). Transmitted by infected female Anopheles mosquito (c). Parasite invades red blood cells (d). Chills and fevers as red blood cells burst

47. Life cycle of Plasmodium vivax which causes Malaria

48. (2). Pneumocystis carinii causes the type of pneumonia seen in AIDS patients (3). Toxoplasma commonly transmitted by cat feces; can be harmful to a developing fetus

50. c. Ciliates, Dinoflagellates, and apicomplexans are alveolates—have sacs under the plasma membrane.