1. Kingdom Fungi

2. The Characteristics of Fungi
Body form
unicellular
Multi-cellular

3. Mycelium – Branched Hyphae
fruiting bodies
both are composed of hyphae
Mycelium – Branched Hyphae

4. The Characteristics of Fungi
Heterotrophic -
Saprophytes or saprobes –
Symbionts -
Parasites –
Parasites that cause disease are called pathogens.

5. The Characteristics of Fungi
Heterotrophic - 'other food'
Saprophytes or saprobes - feed on dead tissues or organic waste (decomposers)
Symbionts - mutually beneficial relationship between a fungus and another organism
Parasites - feeding on living tissue of a host. 
Parasites that cause disease are called pathogens.

6. Heterotrophic by Absorption
Fungi get carbon from organic sources
Hyphae release enzymes
Enzymatic breakdown of substrate
Products diffuse back into hyphae
Enzymatic breakdown
Most enzyme release (and absorption) at tips
Proteins and other materials synthesized by the entire mycelium are channeled by cytoplasmic streaming to the tips of the extending hyphae.
Nucleus hangs back
and “directs”
Products
Enzymes
Product diffuses back
into hypha and is used

7. Hyphae Tubular Hard wall of chitin Grow at tips
Chitin is the same material used by Arthropods (Insects, crabs, etc.) in their exoskeletonsa
Nuclei of fungi are hard to see without stains

8. Hyphal growth Hyphae grow from their tips
Mycelium = extensive, feeding web of hyphae
Mycelia are the ecologically active bodies of fungi
This wall is rigid
Only the tip wall is plastic and stretches

9. Modifications of hyphae

10. Fungi as Saprobes and Decomposers

11. Fungi as Symbionts (Mutualism)

12. Lichens “Mutualism” between Fungus – structure
Alga or cyanobacterium – provides food
Thallus is a plant-like body that doesn’t have roots, stems or leaves
Thallus doesn’t look like either partner
Dual nature of thalli was not fully understood until early 1900’s
Fungus gives the name to the lichen (by agreement)
Fungus usually, but not always, an Ascomycote (in 8+ independent orders)
Algae green. If bluegreen bacteria present, lichens fix nitrogen (turn atmospheric nitrogen into amino acid nitrogen in proteins)

13. Lichen internal structure
The nature of lichen symbiosis is may also be described as mutual exploitation instead of mutual benefit.
Lichens live in environments where neither fungi nor algae could live alone.
While the fungi do not not grow alone in the wild, some (but not all) lichen algae occur as free-living organisms.
If cultured separately, the fungi do not produce lichen compounds and the algae do not “leak” carbohydrate from their cells.
In some lichens, the fungus invades algal cells with haustoria and kills some of them, but not as fast as the algae replenish its numbers by reproduction.
Lobaria oregana prefers old-growth conifer canopies in forests with clean air.
Lichens are nature’s biological indicators of pollution and air quality.
Lobaria

14. Fungi as Parasites & Pathogens

15. Fungi are Spore-ific!!!
Spores - asexual (product of mitosis) or sexual (product of meiosis) in origin.

16. Reproduce by spores Formed: Directly on hyphae
Fungi reproduce by releasing spores that are produced either sexually or asexually.
The output of spores from one reproductive structure is enormous, with the number reaching into the trillions.
Dispersed widely by wind or water, spores germinate to produce mycelia if they land in a moist place where there is food.
Penicillium hyphae with conidia

17. Hyphal growth from spore
germinating
spore
Fungal mycelia can be huge, but they usually escape notice because they are subterranean.
One giant individual of Armillaria ostoyae in Oregon is 3.4 miles in diameter and covers 2,200 acres of forest,
It is at least 2,400 years old, and weighs hundreds of tons.
(Actually noone has seen this of this extent – but cultures have been taken from soil over that area and all isolates have been found to be the same individual)
Ten cubic centimeters of rich organic soil may have fungal hyphae with a surface area of over 300 cm2
mycelium
Mycelia have a huge surface area

18. The Characteristics of Fungi
Classified by how they reproduce.
100,000 Species (estimated 1.5 million species total).
Found everywhere
Cell wall present, composed of cellulose and/or chitin.
Food storage - generally in the form of lipids and glycogen.
Eukaryotes - true nucleus and other organelles present.
All fungi require water and oxygen.

19. Ascomycota – “sac fungi”
Sexual Reproduction – asci (sing. = ascus) - SAC
Asex. Reprod. – common
Cup fungi, morels, truffles
Important plant parasites & saprobes
Yeast - Saccharomyces
Decomposers, pathogens, and found in most lichens
Mycologists have described over 60,000 species of ascomycetes, or sac fungi.
Ascomycota tend to grow from spore to spore in one year and relate well to living plant tissues
There is diverse form in the growth and fruiting structures – yeasts to morels, many intermediate (and small)
Asexual reproduction by conidia (externally produced, not in sporangia)
Half of the Ascomycota form lichens (evolved 8 or more times in different orders) but not all lichens are Ascomycotes
A cluster of asci with spores inside

21. Sac fungi diversity
This begins the first of several photographic reviews of fungal diversity. Enjoy the pictures and try and get a feeling of some of the different forms these fungi take and their roles in the environment.

22. Basidiomycota – “club fungi”
Sexual Reproduction – basidia - CLUB
Asexual reprod – not so common
Rusts & smuts –plant parasites
Mushrooms, puffballs
Enzymes decompose wood, leaves, and other organic materials
Asexual spores conidia
Ecologically important on wood as decomposers and parasites
Half the mushrooms form mycorrhizas
SEM of basidia and spores

23. Bioluminescence in Mycena

24. Deuteromycota – Form Phylum “Imperfect Fungi”
Fungi that seldom or never reproduce sexually.
Asexual reproduction by vegetative growth and production of asexual spores common.

25. Yeasts Single celled fungi Adapted to liquids Plant saps Water films
Moist animal tissues
Bread and wine yeast, the budding yeast, Saccharomyces
Easily cultured. For a time, this was the most important organism for studying the molecular genetics of eukaryotes
Thus, Saccharomyces is arguably the most important organism known to humans
Candida causes diseases of humans, usually experiencing chemical imbalance or immune problems
Candida
Saccharomyces

26. Molds Rapidly growth Asexual spores Many human importances
Food spoilage
Food products
Antibiotics, etc.
Noble Rot - Botrytis
A mold is a rapidly growing, asexually reproducing fungus.
The mycelia of these fungi grow as saprobes or parasites on a variety of substrates.
Also used in foods (Blue cheese, Tempeh) and in industrial production of drugs
Early in life, a mold, a term that applies properly only to the asexual stage, produces asexual spores.
Later, the same fungus may reproduce sexually, producing zygosporangia, ascocarps, or basidiocarps
Some molds go through a “fake sex” process

28. HUMAN-FUNGUS INTERACTIONS
Beneficial Effects of Fungi
Decomposition - nutrient and carbon recycling.
Biosynthetic factories. Can be used to produce drugs, antibiotics, alcohol, acids, food (e.g., fermented products, mushrooms).

29. Harmful Effects of Fungi
Destruction of food, lumber, paper, and cloth.
Animal and human diseases, including allergies.
Toxins produced by poisonous mushrooms and within food (e.g., grain, cheese, etc.).
Plant diseases.