1. Kingdom Protista
1. Algae

2. Characteristics of Algae
Autotrophic
Not plants: reclassified. Why?
Often contain pyrenoids
Pyrenoids are biochemical compartments within the algal equivalent of chloroplasts
Function not completely understood. May play a role in carbon concentration
In other words, they don’t possess plant-like chloroplasts

3. Significance of Algae
Represent the transition from unicellular to multicellular
Are most likely the ancestors of plants
Are major contributors to early oxygenation of the environment
Begin the move away from completely aquatic environments

4. Structure of Algae Thallus or body Unicellular or multicellular
Colonial: Volvoz
Filamentous: Spirogyra
Multicellular: Ulva
Asexual and sexual reproduction

5. General structure

6. Phylums Phylum Chlorophyta Phylum Phaeophyta Phylum Rhodophyta
Phylum Bacillariophyta
Phylum Dinoflagellata
Phylum Chrysophyta
Phyla Euglenohyta

7. Phylum Chlorophyta
Look familiar?

8. Continued… Green algae Many different forms
Gave rise to land plants – why?
Analogues of choroplasts contain a and b cholorphyll
Have carotenoids
Cell walls of cellulose

9. Ulva

10. Colonial Chlorophyta

11. Phylum Phaeophyta Brown algae Marine Seaweed and kelps
Cooler areas of ocean
Fucoxanthin pigment
Store food as laminarin
ALL multicellular
Stemlike stipe
Leaflike region called blade

13. Phylum Rhodophyta Red algae but colors vary Marine seaweeds
Smaller than brown algae and live in deeper waters
Phycobilins – pigment for absorbing light
Some coated with polysaccharide carageenan – cosmetics, gel capsules, cheeses
Agar – extracted from cell walls of red algae

16. Phylum Bacillariophyta
Diatoms (along with radiolaria)
Shells fit together like a box with a lid
Centric and pennate
Main component of phytoplankton
Diatomaceous earth

18. Phylum Dinoflagellata
Dinoflagellates
Small, unicellular
Most photosynthetic
Some bioluminescent
Red tide a problem

21. Phylum Chrysophyta Golden algae Most fresh water Form cysts 2 flagella
Carotenoids give color
Important for formation of petroleum deposits

25. Phylum Euglenophyta Euglenoids
Plant-like and animal-like characteristics
Many have cholorphyll and are photosynthetic
No cell wall, motile
Most live in fresh water
See picture on page 533

26. Euglena: A headache for biologists
Why?
Is it a plant?
Is it an animal?
A good example that shows that classification is not clearly compartmentalised. The lines between major groups of organisms are very blurred

29. Fungus-like protists Slime molds: Phylum acrasiomycota
Cellular slime molds
Amoeboid movement
Phylum Myxomycota
Plasmodial slime molds
Mass of plasmodium
Water molds
Phylum Oomycota
Blight
Phylum Chytridiomycota
Chytrids
Zoospores with one flagellum
Maybe fungi?

30. Slime molds

31. Water molds

32. Chytrids