1. Biology I Chapter 25
Protists

2. Do Now
What organelle contains the cell’s DNA and is the control center of the cell?
Nucleus

3. Characteristics Introduction to Protists
Protist-Single-celled or simple multicellular eukaryotes that don’t fit in any other kingdom.
Emerged 2 billion years ago
The oldest eukaryotic cells were protists

4. Unicellular or Multicellular
Most are unicellular
Some are colonial and form colonies in which several cells are joined into a larger body.

5. Autotrophs Heterotrophs Both
Nutrition
Autotrophs
Heterotrophs
Both

6. Motility Flagella-long, whip-like tail
Cilia-shorter hairs, often in rows
Pseudopodia-”false feet”

7. Asexual Reproduction
Binary fission-a single Protist cell divides into two cells.
Multiple fission-a form of cell division that produces more than two
offspring.

8. Sexual Reproduction
Conjugation-The process in which two Protists come together after meiosis to exchange parts of their genetic material

9. Do Now
What is an organism that feeds on another organism, usually without killing it?
Parasite
What is the organism on which a parasite lives?
Host

10. Do Now
Explain the two main difference between prokaryotes and protists.

11. Phylum Protozoa
Pseudopodia-large, rounded cytoplasmic extensions that function both in movement and feeding
Amoeboid movement-a form of the internal flowing of a cell’s cytoplasm
Amoeba Eats
Amoeba Moves
Death

12. Some sarcodines have protective shells called tests.
Phylum Protozoa
Some sarcodines have protective shells called tests.

13. Phylum Ciliophora Cilia vs. Flagella
Contractile vacuole-squeezes the water out of the cell.
Contractile Vacuole
Macronucleus-contains multiple copies of DNA
Micronucleus-participates in the exchange of genetic material during conjugation.

15. Phylum Sarcomastigophora
African Sleeping Sickness
Trypanosoma
Carried by the Tsetse fly
Cause sleeping sickness-fever, lethargy, mental deterioration, and coma.

16. Phylum Apicomplexa Adult forms have no means of locomotion.
All are animal parasites
Have killed more people than any other group of pathogens on Earth.

17. Phylum Apicomplexa Malaria Carried by mosquitoes Symptoms:
headache and fatigue
follow a cycle
include severe chills and fever.
The protist that causes malaria reproduces in the red blood cells of a human.

18. Phylum Apicomplexa Leishmaniasis Carried by the sand fly Causes boils
Infects the liver, spleen, bone marrow, and causes death.
Curse of the Lost City of the Monkey Gold

19. Algae Autotrophic protists. Lack specialized tissues
Although algae are relatively unspecialized, they may have structures specialized for
Anchoring to the ocean bottom.
Reproduction.
Movement.

20. Phylum Chlorophyta (Green Algae)
Green algae and plants
Have photosynthetic pigments
Use starch to store food.
Have cell walls made of cellulose.

21. Phylum Phaeophyta (Brown Algae)
Include seaweeds and kelps
Used as food
Sargassum

22. Phylum Rhodophyta (Red Algae)
Live at depths where algae lacking red pigments cannot survive
Used as a thickening agent in ice cream, pudding, and icing. (carrageenan)

23. Phylum Bacillariophyta (Diatoms)
Important producers in food webs
Most essential to the production of photosynthetic products and oxygen for Earth’s heterotrophs
Diatomaceous earth can be used to produce detergents, paint removers, and toothpaste.

24. Phylum Dinoflagellata (Dinoflagellates)
Bioluminescence-the production of light by means of a chemical reaction in an organism
Red Tide-when populations of dinoflagellates boom and cause the water to turn brownish red

27. Glowing water
Waves

28. Phylum Chrysophyata (Golden Algae)
Played a role in the formation of petroleum deposits

29. Phylum Euglenophyta (Euglenoids)
Autotrophic and Heterotrophic
Euglena

30. Do Now How do we classify animal-like protists?
How do we classify plant-like protists?

31. Phylum Myxomycota (Plasmodial Slime Mold)
Mass of cytoplasm that can ooze around obstacles
Found on the floor of a forest
The feeding stage of a plasmodial slime mold can be described as multinucleate.
Slime Mold

33. Phylum Dictyostelida (Cellular Slime Mold)
A pseudoplasmodium is a feeding-stage structure.
Take up food from their environment by the process of phagocytosis.
Both types of slime molds produce haploid spores in a fruiting body when they reproduce.
Life Cycle

34. Phyla Oomycota and Chytridomycota (Water Molds)
Most are free-living and aquatic, but some are parasitic.

35. Protists in the Enviornment
Environmental roles of protists
Produce large amounts of atmospheric oxygen.
Photosynthetic protists are at the base of many food webs.
Form important symbiotic relationships with other organisms.

36. Crash Course