Kingdom Fungi

1. Kingdom Fungi Mushrooms, mould, and mildew Fungi in action

2. Characteristics of Fungi • In partners or as a group – what characteristics define a fungus (pl)? • If you said: • Eukaryotic • Heterotrophic, but do not have an internal digestive system (have external digestion) • Non vascular (no root system) • Reproduce sexually and asexually You’d be right!

3. Wait...Fungi aren’t plants? Fungi Non-vascular system Heterotophic Cell wall is composed of chitin • Plants • Have a root system • Autotrophs • Cell wall composed of cellulose

4. Structure of Fungi • Some fungi are single-celled • They are called yeasts • Valuable economically – can you think why?

5. Structure of Fungi • Most fungi are multi-cellular • Body of a fungi generally occurs below ground • Body = mycelium = a branching, mesh-like network of hyphae

6. Structure of Fungi cont. • An individual filament is called a hypha (hyphae (pl)) • One long continuous multicellular structure

7. Structure of Fungi cont. • So what is a ‘mushroom’? • It is the spore producing reproductive structure of a fungus, which is called the fruiting body • Made of hyphae that are densely packed together

8. Fungal Nutrition • Fungi release enzymes into their surrounding • Enzymes break down the food externally • Fungi then absorb the nutrients that have been released by the enzymes through its cell membrane • One way of classifying fungi is through the four different ways that they obtain nutrients

9. Fungal Nutrition • Parasitic • Fungi absorbs nutrients from the living cells of a host organism • Results in death of the host

10. Fungal Nutrition • Predatory • Soil fungi whose mycelia have specialized structures for trapping prey

11. Fungal Nutrition • Mutualistic • Fungi that have partnerships with other organisms (e.g. Plants, protists or animals) • Both organisms involved in the partnership benefit from the relationship

12. Fungal Nutrition • Saprobial • Fungi that feed on dead or decaying organic matter • i.e. They are decomposers • Very important in nutrient recycling

13. Learning Check • What is mycelium and where is it found? • When you see a mushroom growing from a dead log, which part of the fungus are you observing?

14. Fungal Classification • 5 Major Phlya • Phylum Chytridiomycota (chytrids) • PhlyumZygomycota (zygomycetes) • Phylum Deuteromycota • Phylum Ascomycota (ascomycetes) • Phylum Basidiomycota (basidiomycetes) • Based on differences in reproduction and the structure of the fruiting body they produce

15. Fungi Imperfecti (Deuteromycota) • Not known to reproduce sexually • Generally types of moulds • E.g. Penicillium mould; mould in blue cheese

16. Chytrids (P. Chytridomycota) • Mostly unicellular • Aquatic species (marine or freshwater) • Spores have flagella (motile) • Parasitic or saprophytes

17. Zygospore Fungi (P. Zygomycota) • Multicellular and mostly terrestrial (soil) • Include familiar bread and fruit moulds • Generally reproduce asexually

18. Zygospore Fungi (P. Zygomycota) • Reproduce sexually in unfavourable conditions to produce zygospores • Diploid structure (2n) that develops after two haploid (n) hyphae of opposite types combine their nuclei. Thick wall develops around nuclei to protect it.

19. Sac Fungi(P. Ascomycota) • Largest fungi group • Develop small finger-like sacs called asci (contain spores) during sexual reproduction (similar to creation of zygospores) • Saprophyte and parasites • Includes yeasts, which reproduce by budding

20. Club Fungi (P. Basidiomycota) • Includes ‘mushrooms’, puffballs, and stinkhorns • Most are decomposers, some form symbiotic (mutualistic) relationship with plants • E.g. lichen

21. Club Fungi (P. Basidiomycota) • Fruiting bodies release spores called basidiospores from basidia (club-shaped hypha)

22. Reproduction • Asexual • Budding – a smaller cell develops while attached to a parent cell. Eventually, small cell is pinched off of parent cell to produce a new individual

23. Reproduction • Asexual • Fragmentation – a piece of mycelium breaks and forms a new individual • Spore production • Sexual reproduction - also involves spore production and often the creation of a fruiting body above ground • Fig3.21 (hand-out)

24. The Importance of Fungi • Fungi are: • Decomposers – one of the most important groups for recycling materials along with Bacteris • Form symbiotic relationships – esp. with plants. Without these relationships plant growth and productivity would be reduced • Food source (e.g. Blue cheese, mushrooms) and used in food production (bread, beer)

25. The Importance of Fungi • Fungi are: • Sources of antibiotics (medicine) (e.g. Penicillin). The discovery of antibiotics revolutionized health care worldwide. • Biocontrol – use fungi that target insects to control crop pests (e.g. Chinese caterpillar fungus; control of California potato beetles). This is cheaper and less damaging to the environment than using chemical pesticides

26. The Importance of Fungi • Fungi • Cause animal and plant disease (e.g. Every year 10 – 50% of world’s fruit harvest is destroyed by fungi!) (e.g. Athlete’s foot, ringworm) • Food spoilage (mould)

27. Meet the worlds largest organism Honey mushrooms – give an inkling of what is below. http://www.scientificamerican.com/article.cfm?id=strange-but-true-largest-organism-is-fungus