- Protists are a diverse group of mostly single-celled eukaryotes that are classified into several different kingdoms. - They exhibit an enormous diversity of structures and metabolic capabilities, including photosynthesis, heterotrophy, and mixotrophy. - Common protist groups discussed in the document include protozoa, alveolates, stramenopiles, and chlorophytes. Many important parasites are protists, including those that cause malaria, African sleeping sickness, and Chagas disease.

1. Kingdom Protista
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Mr. Nattapong Boonpong (B.Ed.)
Phlabphlachai Phitthayakhom School

2. Overview: A World in a Drop of Water
• Even a low-power microscope
– Can reveal an astonishing menagerie of organisms
in a drop of pond water
50 m

3. The Protozoa

4. Characteristic Protist
• These amazing organisms
– Belong to the diverse kingdoms of mostly single-
celled eukaryotes informally known as protists
• Advances in eukaryotic systematics
– Have caused the classification of protists to change
significantly.
• Protists are more diverse than all other eukaryotes
– And are no longer classified in a single kingdom
• Most protists are unicellular
– And some are colonial or multicellular

5. Characteristic Protist (Continuous)
• Protists, the most nutritionally diverse of all
eukaryotes, include
– Photoautotrophs, which contain chloroplasts
– Heterotrophs, which absorb organic molecules or
ingest larger food particles
– Mixotrophs, which combine photosynthesis and
heterotrophic nutrition
• Protist habitats are also diverse in habitat
• And including freshwater and marine species

6. Habitat of Protist

7. Reproduction of Protist
• Reproduction and life cycles
– Are also highly varied among protists, with both
sexual and asexual species

8. A Sample of Protist Diversity

9. Protozoa
• Eukaryotic
• Unicellular
• Chemoheterotrophs
• Vegetative form is a
trophozoite
• Asexual reproduction
by fission, budding, or
schizogony
• Sexual reproduction
by conjugation
• Some produce cysts

10. I. Diplomonadida & Parabasala
• No mitochondria, ER, golgi complex, & centriole
• Multiple flagella
• Are adapted to anaerobic environments
• Lack plastids

11. Diplomonads & Parabasalids
• Diplomonads
– Have two nuclei and multiple flagella
5 µm
Giardia intestinalis, a diplomonad (colorized SEM)

12. Giardiasis; Giardia lamblia

13. Diplomonads & Parabasalids
• Parabasalids include trichomonads
– Which move by means of flagella and an undulating
part of the plasma membrane
– Have parabasal body Flagella
Undulating membrane 5 µm
Trichomonas vaginalis, a parabasalid (colorized SEM)

14. Trichomoniasis; Trichomonas vaginalis

15. Diplomonads & Parabasalids
• Have one nucleus and
multiple flagella
• Have parabasal body
Trichonympha sp., a parabasalid

16. II. Euglenozoa
• Move by flagella
• Photoautotrophs
– Euglenoids
• Chemoheterotrophs
– Trypanosoma
• Undulating membrane, transmitted by vectors
– Leishmania
• Flagellated form in sand fly vector, ovoid form in
vertebrate host

17. Euglenozoa
Euglenoids; Euglena

18. การเคลื่อนที่ของยูกลีนา

19. Kinetoplastids
• Kinetoplastids
– Have a single, large
mitochondrion that
contains an organized
mass of DNA called a
kinetoplast
– Include free-living
consumers of bacteria in
freshwater, marine, and
moist terrestrial
ecosystems

20. Kinetoplastids

21. Kinetoplastids
• The parasitic kinetoplastid Trypanosoma
– Causes sleeping sickness in humans
9 m

22. Kinetoplastids
Trypanosoma brucei gambiense
Trypanosoma brucei rhodesiense
Trypanosoma cruzi
Trypanosomiasis, African (African sleeping sickness)
Trypanosomiasis, American (Chagas disease)

23. Trypanosoma

24. Trypanosomiasis (African Sleeping Sickness);
T. brucei gambiense & T. brucei rhodesiense

25. Trypanosomiasis (American Chagas Disease)

26. III. Alveolata
• Alveolates have sacs beneath the plasma membrane
• Members of the clade Alveolata
– Have membrane-bounded sacs (alveoli) just under
the plasma membrane
0.2 µm Alveoli
Flagellum

27. Alveolata: Dinoflagellate
• Dinoflagellates
• Cellulose in plasma
membrane
• Unicellular
• Chlorophyll a and c,
carotene, xanthins
• Store starch
• Some are symbionts in
marine animals
• Neurotoxins cause
paralytic shellfish
poisoning

28. Alveolata: Dinoflagellate

29. Dinoflagellate: Red tide Bloom
Dinoflagellate หลายชนิด เช่น Gymnodinium &
Trichodesmium จะทาให้เกิดปรากฏการณ์“red tide”ในทะเล
และมหาสมุทรบางแห่ง และสร้างสารพิษออกมา ทาให้สัตว์นา
ตายครังละมาก ๆ โดยจะออกฤทธิ์ที่ระบบประสาท นอกจากนี
Gymnodinium & Gonyaulax ยังสร้างพิษทาให้ปลาตายและ
มนุษย์ที่ได้รับสารพิษเข้าไปจะเสียชีวิตได้

30. Dinoflagellate
Peridinium Trichodesmium
Gymnodinium Gonyaulax

31. Alveolata: Apicomplexa
• Nonmotile
• Intracellular parasites
• Complex life cycles
• Plasmodium
* Plasmodium vivax
* Plasmodium malariae
* Plasmodium ovale
* Plasmodium falciparum

32. Alveolata: Apicomplexa; Plasmodium sp.
Sporozoites 1 Infected mosquito bites 2 Sporozoites
in salivary human; sporozoites undergo
gland migrate through schizogony in
bloodstream to liver cell;
liver of human merozoites
are produced
9 Resulting sporozoites
migrate to salivary glands
of mosquito
3 Merozoites
Sexual released into
reproduction bloodsteam from
liver may infect
Asexual new red blood
8 In mosquito’s cells
Zygote digestive tract, reproduction
gametocytes
unite to form Intermediate host
Female
gametocyte zygote
4 Merozoite develops
Male into ring stage in red
gametocyte blood cell
Ring 5 Ring stage
stage grows and
Definitive host divides,
7 Another mosquito bites producing
6 Merozoites are released merozoites
infected humnan and when red blood cell
ingests gametocytes ruptures; some merozoites
infect new red blood cells,
and some develop into
male and female
gametocytes Merozoites

33. Alveolata: Apicomplexa; Plasmodium sp.

34. Apicomlexa; Malaria

35. Alveolata: Ciliates
• Ciliates, a large varied group of protists
– Are named for their use of cilia to move and feed
– Have large macronuclei and small micronuclei
• The micronuclei
– Function during conjugation, a sexual process that
produces genetic variation
• Conjugation is separate from reproduction
– Which generally occurs by binary fission

36. Alveolata: Ciliates
• Structure and Function in the Ciliate Paramecium caudatum
FEEDING, WASTE REMOVAL, AND WATER BALANCE
Paramecium, like other freshwater Contractile Vacuole Paramecium feeds mainly on bacteria.
protists, constantly takes in water Rows of cilia along a funnel-shaped oral
by osmosis from the hypotonic environment. groove move food into the cell mouth,
Bladderlike contractile vacuoles accumulate where the food is engulfed into food
excess water from radial canals and periodically vacuoles by phagocytosis.
expel it through the plasma membrane.
Oral groove
Cell mouth
Thousands of cilia cover
50 µm Food vacuoles combine with
the surface of Paramecium.
lysosomes. As the food is digested,
the vacuoles follow a looping path
Micronucleus through the cell.
Macronucleus
The undigested contents of food
vacuoles are released when the
vacuoles fuse with a specialized
region of the plasma membrane
that functions as an anal pore.

37. Alveolata: Ciliates
CONJUGATION AND REPRODUCTION
1 Two cells of compatible 2 Meiosis of micronuclei
mating strains align side produces four haploid 3 Three micronuclei in each cell
by side and partially fuse. micronuclei in each cell. disintegrate. The remaining micro-
nucleus in each cell divides by mitosis.
MEIOSIS
4 The cells swap
one micronucleus.
Macronucleus
Haploid
micronucleus
Compatible Diploid
mates micronucleus
Diploid
micronucleus
MICRONUCLEAR
FUSION
5 The cells
separate.
9 Two rounds of cytokinesis 8 The original macro- 7 Three rounds of 6 Micronuclei fuse,
partition one macronucleus nucleus disintegrates. mitosis without forming a diploid Key
and one micronucleus Four micronuclei cytokinesis micronucleus.
into each of four daughter cells. become macronuclei, produce eight Conjugation
while the other four micronuclei.
remain micronuclei.
Reproduction

38. Ciliates
Stentor Paramecium

39. Ciliates
Stentor polymorphus Stentor roeseli Epistylis rotans
Vorticella Paramecium bursaria Suctoria
Strombidium Trichodina pediculus Euplotes

40. IV. Stramenopila (Algae)
• Stramenopiles have “hairy” and smooth flagella
• The clade Stramenopila
- Includes several groups of heterotrophs as well as
certain groups of algae
• Most stramenopiles
- Have a “hairy” flagellum paired with a “smooth”
flagellum
Hairy
flagellum
Smooth
flagellum
5 µm

41. Algae

42. Stramenopila: Brown algae (Phaeophyta)
• Are the largest and most complex algae
• Are all multicellular, and most are marine
• Brown algae (kelp)
• Cellulose + alginic acid cell
walls
• Multicellular
• Chlorophyll a and c,
xanthophylls; fucoxanthrin
• Store carbohydrates
• Harvested for algin

43. Stramenopila: Brown algae
• Kelps, or giant seaweeds
– Live in deep parts of the ocean

44. Brown algae
Laminaria saccharia - สกัดเอา algin มาทายา อาหาร เส้นใย ยาง สบู่ ฯลฯ
- ใช้ทาปุ๋ย K ได้
Padina & Fucus -ใช้ทาปุ๋ย K ได้
Sargassum (สาหร่ายทุ่น) - มีไอโอดีนสูง และยังให้ algin
Laminaria & Sargassum - สามารถนามาตากแห้ง ต้มนาดื่มแก้ร้อนใน
คอพอก และฟอกเลือด
Giant kelp - สร้างสาร algin มาทายา อาหาร เส้นใย กระดาษ ยาง
สบู่ และเป็นสาหร่ายที่มีขนาดใหญ่ที่สุด เป็นที่อยู่อาศัย
หลบภัยและอาหารของสัตว์นานานาชนิดใต้ท้องทะเล
Laminaria Padina Fucus

45. Brown algae
Sargassum Kelp

46. Brown algae
(a) The seaweed is
grown on nets in
shallow coastal
waters.
(b) A worker spreads
the harvested sea-
weed on bamboo
screens to dry.
(c) Paper-thin, glossy sheets
of nori make a mineral-rich wrap
for rice, seafood, and vegetables
in sushi.

47. Stramenopila: Diatoms (Bacillariophyta)
• Diatoms
• Pectin and silica cell walls
• Unicellular
• Chlorophyll a and c, carotene, xanthophylls
• Store oil
• Fossilized diatoms formed oil
• Produce domoic acid

48. Diatomaceous earth
• Accumulations of fossilized diatom walls
– Compose much of the sediments known as
diatomaceous earth

49. Diatoms
Pinnidaria Navicular
Asterionella Melorista

50. V. Rhodophyta (Red algae)
• Red algae
• Cellulose cell walls
• Most multicellular
• No flagella stage
• Chlorophyll a and d,
phycobiliproteins
(phycocyanin &
phycoerythrin)
• Store glucose polymer
• Harvested for agar and
carrageenan

51. Rhodophyta (Red algae)

52. Red algae
Porphyra (จี่ฉ่าย) - ใส่แกงจืดเป็นอาหาร
Gracilaria (สาหร่ายผมนาง หรือ สาหร่ายวุ้น) - นามาสกัดวุ้นผสมในอาหารเลียงเชือจุลินทรีย์ (agar)
- ใช้เพาะเลียงเนือเยื่อ
- ทาแคปซูลยา ทายา ทาเครื่องสาอางค์ ครีมโกนหนวด ฯลฯ
Chondrus Plumoria Andrus Corellina
Polysiphinia Gelidium Grinnellia
Porphyra Polysiphinia

53. Red algae
Gelidium
Chodrus crispus

54. VI. Chlorophyta (Green algae)
• Green algae
• Cellulose cell walls
• Unicellular, multicellular
or colonial form
• Chlorophyll a and b
• Store glucose polymer
• Gave rise to plants
• Are named for their grass-green chloroplasts
• Are divided into two main groups: chlorophytes
and charophyceans
• Are closely related to land plants

55. Chlorophyta (Green algae)

56. Chlorophyta (Green algae)

57. Chlorophyta (Green algae)

58. Chlorophyta (Green algae)
Spirogyra

59. Chlorophyta (Green algae)
Micrasterias rotata Cell division Micrasterias fimbriata Staurastrum
Hyalotheka dissilens Closterium lunula Staurodesmus convergens Euastrum verrucosum
Volvox aureus Draparnadia platyzonata Mougeotia Pediastrum

60. Chlorophyta (Green algae)

61. Chlorophyta (Green algae)
Chara sp., Overlap between Protista with Plant

62. VII. Mycetozoa (Slim Molds)
• Cellular slime molds • Plasmodial slime molds
– Resemble amoebas, – Multinucleated large
ingest bacteria by cells
phagocytosis – Cytoplasm separates
– Cells aggregate into into stalked sporangia
stalked fruiting body. – Nuclei undergo
– Some cells become meiosis and form
spores uninucleate haploid
spores

63. Cellular Slim Molds

64. Plasmodial Slim Molds

65. Slim Molds

66. Slim Molds

67. Slim Molds

68. Slim Molds

69. Slim Molds

70. Slim Molds

71. Rhizopodium; Amoeba

72. Amoebiasis

73. Acanthamoeba spp. & Balamuthia mandrillaris

74. Entamoeba
• Entamoeba coli - in Large intestine; colon
• Entamoeba gingivalis - in Mouth; teeth & gill
• Entamoeba histolytica - in Small intestine

75. Entamoeba histolytica
• Entamoeba histolytica; Amoebic Dysentery
• Amoeba feeds on RBCs and GI tract tissues
• Diagnosis by observing trophozoites in feces
• Treated with metronidazole

76. The End