1. Ch. 20 Protists

2. Ch. 20 Outline 20-1: The Kingdom Protista
What is a Protist
Classification of Protists
20-2: Animal-like Protists: Protozoans
Zooflagellates
Sarcodines
Ciliates
Animal-like Protists and Disease
Ecology of Animal-like Protists

3. Ch. 20 Outline 20-3: Plant-like Protists: Unicellular Algae
Chlorophyll and Accessory Pigments
Euglenophytes
Chrysophytes
Diatoms
Dinoflagellates
Ecology of Unicellular Algae

4. Ch. 20 Outline 20-4: Plant-like Protists: Multicellular Algae
Red Algae
Brown Algae
Green Algae
Human Uses of Algae
20-5: Fungus-like Protists
Ecology of Fungus-like protists

5. What is a Protist?
Protist: Any eukaryotic organism that is not a plant, animal, or fungus.
Kingdom Protista is the most diverse kingdom. They can be unicellular or multicellular

6. Classification of Protists
One way to classify protists is by how they obtain nutrition:
Heterotrophs – animal like
Autotrophs – plant like
Decomposers/Parasites – fungus like

7. Phyla Tree

8. Zooflagellates
Animal-like protists that swim using a flagella are classified in the Phylum zoomastigma and are often referred to as zooflagellates.
Flagella: Long, whiplike projection that enable movement.

9. Sarcodines
Sarcodines are animal-like protists that use pseudopods for feeding and movement
Ex. Amoebas
Amoebas capture food by surrounding it, then taking it in and forming a food vacuole.
Food Vacuole: small cavity in the cytoplasm that temporarily stores food.

10. Amoeba
Pseudopods

11. Ciliates
Members of the phylum Ciliophora, known as ciliates, use cilia for feeding and movement.
Cilia beat like oars
Ex. Paramecium
Anatomy of a Paramecium
Macronucleus: “Working Library” of a genetic information
Micronucleus: contains a “reserve copy” of all the cell’s genes
Gullet: Indentation on one side of the organisms (food enters here)
Anal Pore: Region where waste is emptied
Contractile vacuole: Expels excess water

12. Paramecium

13. Sporozoans
Members of the Phylum Sporozoa do not move one their own and are parasitic.

14. Animal-like Protists and Disease
Protists can causes some diseases.
Example: Malaria
Caused by the sporozoans Plasmodium, which is carried by the Anopheles mosquito
Plasmodium infects liver cells and RBC’s where it reproduces causing those cells to burst

15. Malaria

16. Ecology of Animal-like Protists
Recycle nutrients in the environment
Serve as food for larger animals
Live symbiotically with other organisms
Ex. Trichonympha live in the guts of termites and enable them to digest wood (by the enzyme cellulase)

17. Chlorophyll and Accessory Pigments
Many protists contain the green pigment, chlorophyll and carry out photosynthesis. One the ways plant-like protists are categorized is by the type of photosynthetic pigment they contain.
Accessory pigments: absorb light at different wavelengths than chlorophyll
Review: The energy from sunlight is used by photoautotrophs to make sugars for food

18. Euglenophytes These protists have two flagella but no cell wall.
Ex. Euglena
Eyespot: Reddish pigment near the gullet
Senses light
Euglena can also be heterotrophic

19. Euglena Chloroplast Carbohydrate storage bodies Gullet Pellicle
Contractile vacuole
Flagella
Eyespot
Nucleus

20. Chrysophytes These protists have gold-colored chloroplasts
Ex. Yellow-green and golden-brown algae

21. Diatoms
Diatoms produce thin, delicate cell walls rich in Silicon (Si) – the main component in glass.
Used in pesticides – Like Shrapnel!

22. Dinoflagellates Many of these are lumniscent.
About half are photosynthetic and half are heterotrophs.
They have two flagella also.

23. Dinoflagellates

24. Ecology of Unicellular Algae
Plant-like protists serve as the base of a food chain in many aquatic ecosystems
Phytoplankton: population of small, photosynthetic organisms found nears the surface of the ocean.
Protists make up much of phytoplankton

25. Agal Blooms
When waste is high the number of plant-like protists increases greatly (since they use the organic matter for food). This is called a bloom
A “red tide” is a bloom of dinoflagellates. They give off a toxin that harms both humans and fish.

26. Red Algae
Red Algae are able to live at great depths due to their efficiency in harvesting light energy. Red Algae contain chlorophyll a and reddish accessory pigments called phycobilins.

27. Brown Algae
Brown Algae contains chlorophyll a and c, as well as a brown accessory pigment called fucoxanthin.

28. Green Algae
Green Algae share many characteristics with plants, including their photosynthetic pigments and cell wall composition.
Pigments: a and b

29. Human Uses of Algae Photosynthesis  oxygen in atmosphere
Chemicals in algae used in medicines
Food source
Chemicals used to make plastics, waxes, paints and more!

30. Fungus-like Protists
Like fungi, funguslife protists obtain their food by digesting outside their bodies (heterotrophs), but they do not have cell walls of chitin like fungi.
Two types of mold:
Slime Molds
Water Molds

31. Water Mold

32. Slime Mold MEIOSIS FERTILIZATION Germinating spore Zygote Spores
Mature sporangium
Feeding plasmodium
Young sporangium
Mature plasmodium
Haploid (N) Diploid (2N)

33. Ecology of Fungus-like Protists
Important recyclers of organic material
Decomposers of dead things!
Some cause plant diseases
Potato Blight in Ireland caused by water mold
Lead to Irish immigration to America