1. Kingdom Protista

2. Kingdom Characteristics
• Eukaryotic
• Mostly unicellular (microscopic)
some are multicellular
• Autotrophic, Heterotrophic, and both
• Most reproduce asexually, but some can use conjugation (exchange of genetic material)
• Cell wall may or may not be present
• Taxonomic Misfits–
Contains all eukaryotic cells that can’t be classified as plant, animal or fungus

3. Evolutionary Importance
Protists are considered to be the ancestors of the three multicellular kingdoms—fungi, plant, animal

4. Major Divisions of Protists
Plant-like Protists (Algae)
Animal-like Protists (Protozoans)
Fungus-like Protists (Slime Molds)

5. Plant-like Protists—Algae
Autotrophic
Contain cell walls
Most are immobile—some are mobile

6. Examples of Plant-like Protists: Green, Red, and BrownAlgae
Cellular Organization:
– Multicellular (Red and Brown)
Green algae can be either
• Nutrition:
Photosynthetic (Autotrophic)
Locomotion:
Non-motile
Habitat:
Red Algae: Marine
Green Algae: Fresh, Marine, Soil
Brown Algae: Marine
Classified by their pigment
Green, Red, or Brown (kelp) Algae
Used in many foods such as pudding, jelly, jelly beans, ice cream, marshmallows, salad dressing

7. Diatoms
• Cellular Organization: – Unicellular • Nutrition: – Autotrophic • Locomotion: - Non-motile • Habitat: – Fresh and Marine • Shells made out of silica (glass-like)

8. Euglenoids
• Cellular Organization: – Unicellular • Nutrition: – Heterotrophic/Autotrophic • Locomotion: - 1 or 2 Flagella • Habitat: – Aquatic • Ex: Euglena

9. Animal-like Protists– a.k.a. Protozoans
• Heterotrophic • All are unicellular • None contain cell walls • Most can move: – Cilia- hair-like projections – Flagella- whip-like tail – Pseudopod- “false foot”

10. Sarcodines- Ameoba
• No cell wall gives them flexibility • Cellular Organization: – Unicellular • Nutrition: – Heterotrophic • Locomotion: -Pseudopods • Habitat: – Fresh and salt water • Some may cause disease (they are parasites)

11. Flagellates
• Cellular Organization: – Unicellular • Nutrition: – Heterotrophic • Locomotion: -flagella • Habitat: -free living and parasitic • Ex: Trypanosomes causes AfricanSleeping Sickness

12. Ciliates
• Cellular Organization: – Unicellular • Nutrition: – Heterotrophic • Locomotion: - cilia • Habitat: - fresh water and marine • Ex: Paramecium, Vorticella and stentor

13. Sporozoans
• Cellular Organization: – Unicellular • Nutrition: – Heterotrophic • Locomotion: -Non-motile • Habitat: -parasitic • Ex: – Plasmodium-Malaria

14. Fungus-like Protists- slime molds
• Heterotrophic decomposers • Contain cell walls • Multicellular • Exist in different forms and produce spores • Reproduce by forming spores • 3 types:water molds, downy mildews, and slime molds

15. Slime Molds
• Cellular Organization: – Multicellular • Nutrition: – Heterotrophic • Locomotion: - amoeboid movement • Habitat: - cool, moist, shady places

16. Watery/Downy Molds
• Cellular Organization: – Multicellular • Nutrition: – Heterotrophic (either parasites or feed on dead organic matter) • Locomotion: - amoeboid movement • Habitat: -cool, moist, shady places • Cause of the Irish potato famine in that killed 1 million people

17. Ecological Importance of Protists
• Autotrophic protists are primary component of PHYTOPLANKTON • They carry out 70 – 80% of the world’s photosynthesis • They are the base of most of the world’s food chains

18. Negative Contributions of Protists
• Many cause disease
– Malaria, sleeping sickness, amebic dysentery, etc.
• Responsible for “Red Tide” that poisons shell fish
• Algae blooms result in fish kills

19. Paramecian Fission (asexual)

20. Paramecium Conjugation
animation
Two individuals line up with each other and make contact with their oral groove,
The micronucleus (2N) undergoes meiosis result-ing in four micronuclei in each of the two cells (N)
3 micronuclei degenerate and are digested by the cell.
The remaining micronucleus in each paramecium divides once again, by mitosis.
By the time this has occurred, most of the cell membrane dividing the two cells is gone.
The two halves (originally two cells) then exchange one of their micronuclei.
The cell membrane between the two halves gets rebuilt and the two cells separate again.
The two haploid micronuclei (one original and one new) fuse into a single diploid micronucleus.
The original macronucleus, disintegrates and gets digested by the cell’s enzymes.
The micronucleus divides by mitosis to produce two identical diploid micronuclei in each individual.
One of the micronuclei then becomes the real micronucleus while the other one grows and becomes the new Macronucleus.