Understanding Protists and Fungi: Functions and Impact

2. Kingdom Protista • Eukaryotic • Most unicellular, some multicellular • Range in size from a microscopic amoeba to giant seaweed • Thought to be the ancestors to all other eukaryotic kingdoms

3. Where are Protists found? • fresh water • salt water • inside organisms

4. Classified by the way they obtain nutrition. • Animal-likeheterotrophs • Plant-likeautotrophs • Fungus-likeexternal digestion

5. 1. Characteristics of Animal-like Protists (aka Protozoans) • Heterotrophs • Unicellular • Classified by the way they move • Ex: pseudopods, flagella, cilia

6. 2. Plant-like protists(aka algae or plankton) • Photoautotrophs • Contain chlorophyll - but no roots, stems, or leaves • Multi- or unicellular

7. 3. Fungus-like Protists • Heterotrophs • Decompose dead organisms • External digestion, then absorb nutrients • Mostly unicellular Downy mildew on soybeans Slime mold

8. Ecological Roles of Protists • Plant-like protists - produce 70% of Earth’s oxygen • Live symbiotically w/other organisms, ex. Trichonymphalive inside termites help digest wood • Fungus-like protists recycle nutrients • phytoplankton and zooplankton - food source for larger sea animals • Human uses of algae - sushi wraps, agar plates, ice cream, salad dressing, medicines, paints, polishes • Cause mildew and blight in grapes & tomatoes • Irish potato famine → immigration to US

9. Disease Causing Protists Entamoeba – causes amebic dysentery, severe diarrhea and intestinal bleeding that can lead to death Trypanosoma – causes African Sleeping Sickness, uncontrolled sleepiness, high fever that can lead to death, transferred by the teste fly Giardia – causes Giardiasis, fatigue and diarrhea due to contaminated food. Plasmodium – causes Malaria, flu-like symptoms, transferred through infected mosquitos

11. Kingdom Fungi • Eukaryotic • Heterotrophs - use extracellular digestion (excrete enzymes and absorb nutrients) • Cell walls made of chitin • Some unicellular (ex. Yeast) • Most multicellular

12. Where are fungi found? Everywhere • air, water, soil • people (athlete’s foot, yeast infection, ringworm) • foods (bread-yeast, cheese, mushrooms)

13. Fruiting body – above ground, produce reproductive spores Hyphae: threadlike filaments (one-cell thick) Mycelium - a network of hyphae below ground

14. 3 feeding relationships • Decomposers - recycle nutrients • Parasitism - corn smut, mildews, wheat rust, yeast infections, athlete’s foot, ringworm • Mutualism - 2 examples

15. Symbiotic Relationships of Fungus • Mycorrhizae - fungus & plant roots • Fungus covers roots increasing surface area for absorbtion • Plant provides food to fungi • Ex. Orchids • Lichens - fungi & algae or cyanobacteria • Algae provide food by photosynthesis while fungi provides water & minerals

16. Fungi Reproduction • Asexual - through fragmentation (hyphae break off & grow new mycelia)or budding. • Sexual – through spores produced by fruiting body

17. Examples

18. Human and Ecological Importance • Decomposers - Recycle nutrients • Penicilium mold used to create antibiotics • Some used as a food source, ex. yeast