1. Mushrooms, mould, and mildew Fungi in action
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?
Have a root system
Autotrophs
Cell wall composed of cellulose
Fungi
Non-vascular system
Heterotophic
Cell wall is composed of chitin

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
Where do you think most of the body of a fungus occurs? Above ground or below ground

6. Structure of Fungi cont.
An individual filament is called a hypha (hyphae (pl))
One long continuous multicellular structure
Hyphae have a structure unlike plant or animal cells; consist of long tubes of cytoplasm containing many nuclei; cytoplasm contained by a cell wall that consists of chitin; tubes separated into cell-like compartments by cell walls called speta (septum) -

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
Hyphae have a structure unlike plant or animal cells; consist of long tubes of cytoplasm containing many nuclei; cytoplasm contained by a cell wall that consists of chitin; tubes separated into cell-like compartments by cell walls called speta (septum) -

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
Hyphae have a structure unlike plant or animal cells; consist of long tubes of cytoplasm containing many nuclei; cytoplasm contained by a cell wall that consists of chitin; tubes separated into cell-like compartments by cell walls called speta (septum) -

9. Fungal Nutrition Parasitic
Fungi absorbs nutrients from the living cells of a host organism
Results in death of the host
In this case, fungi generally lives inside the host organism

10. Fungal Nutrition Predatory
Soil fungi whose mycelia have specialized structures for trapping prey
Nematode caught in constricting rings of hyphae

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
Another example = relationship many fungi have with plants. In this case, mycelia covers plant roots – increase surface area of roots , allowing plants to take in more nutrients and provide fungus with sugar (food)
Eg. Lichen – an organism that results from a mutualistic relationship b/w a fungus and a photosynthetic plant or alga

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)
Phlyum Zygomycota (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
Sexual reproduction involves the fusion of two mating types to form spore-bearing asci

20. Club Fungi (P. Basidiomycota)
Includes ‘mushrooms’, puffballs, and stinkhorns
Most are decomposers, some form symbiotic (mutualistic) relationship with plants
E.g. lichen
Sexual reproduction involves the fusion of two mating types to form spore-bearing asci

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
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.