KINGDOM FUNGI
Fungus…
What are they? How many are there?
Where do we find them? Why do they exist? What do they do? How are they important? How are they different?
Why? How do they reproduce?
Survive?
Phylogeny of Fungus
Which kingdom is more closely related to fungi?
Why do you think so?
Kingdom Fungi
Eukaryote >100 000 species
identified Few unicellular, majority
multi-cellular Similar to plants, but no
chlorophyll Heterotrophic – absorb
external nutrients (osmotrophic)
Important for ecosystems as breakdown organic matter and recycle nutrients
Structure of Fungi
Uni-Cellular (i.e. yeasts) - have individual ovoid / cylindrical cells
Multi-Cellular (majority) – structurally diverse, but general shape
Structure of Multi-Cellular Fungus
Body form diverse, but general shape
Above ground; edible; “fruiting body” of fungus
Underground network; body of fungus
Fungal Structure
Hyphae form the “fuzz” often associated with mould.
Also form reproductive structures of many fungi.
Hyphae grow at their tips, nuclei multiply by mitosis.
Mycelium forms body of fungus below ground.
Structure of Multi-Cellular Fungus
Hyphae: threadlike tubes that produce enzymes
for digestion.
Reproductive Structure: produces
tiny cells called spores.
The morphology strives to enhance their ability to absorb nutrients from their surroundings
20 mm
Mycelium
Fungal Nutrition
Release digestive enzymes to break down food externally, then absorb nutrients
4 methods of nutrient uptake: Parasitic Predatory Mutualistic Saprobic
Fungal Nutrition
Parasitic Fungi
∼30% known parasitic (mostly on/ in plants) Some release toxic chemicals called
neurotoxins; result in poisoning or death Examples:
Ergots Tar spot fungus
Corn smut Cordyceps fungus growing through its host’s body
Mutualistic Fungi
>80% of all land plants have this relationship with fungi
Receive energy (carbohydrates) directly from a plant
Examples: mycorrhizal fungi (grows in and around plant roots) Plant provides carbohydrates (glucose)
Fungi provides minerals (P,K, N) & water from the soil.
Mycorrhizal fungi
Saprobic (Decomposers)
breakdown complex molecules into sugars or consume sugars found in environment
Examples:
common bread mold (eats carbs in bread)
shelf fungi on logs (eats carbs in cell wall of wood)
white button mushrooms in store (eats sugars and cellulose in dung)
Saprobic (Decomposers)
(a) Fly agaric, common species in conifer forests in the N. hemisphere
(b) Maiden veil fungus (Dictyphora) - odor like rotting meat
(c) Shelf fungi, important decomposers of wood
(d) Puffballs emitting spores
Fungal Reproduction
Complicated; some involved both stages of asexual and sexual.
Asexual Sporulation (spores) Budding (smaller cell
develops while attached to parent
Fragmentation (piece of mycelium break off and forms new individual)
In fungi, most nuclei are haploid (single set of chromosomes)
Fungal Reproduction
Sexual Use of fruiting
bodies, which differ
4 phyla of fungi that reproduce sexually
Fungi Kingdom
There are five different phylain the Kingdom Fungi
Lichens
Composite organism depends on 2-way relationship Fungus + photosynthetic organism (e.g.
cyanobacteria, unicellular green algae)
Lichens
Can occur in harsh environments (tundra, deserts, rocky coasts), also in rain forest, temperate woodlands and bare rock
Important food source Vulnerable to environmental
disturbance, ∴ used to assess effects of pollution
Other uses: dyes, perfumes, litmus paper
Why are Fungi Important?
Important food source and in food processing Yeast Beer and Wine Bread Mushrooms White button,
crimini,portabella Truffles, chanterelles Mycoprotein Fermented tofu/bean curd
Cheese (ripening-outide, given inside flavour) e.g. Blue cheese Soy sauce, Tempeh Citric acid (soft drinks) Flavours (menthol, tarpenes)
Why are Fungi Important?
Assist in plant growth and decomposition to cycle nutrients in the biosphere.
Can breakdown lignin and cellulose
Why are Fungi Important?
Cause variety of plant, animal and human diseases Respiratory diseases, fungal infection Potato famine, black mould
Oral Yeast Infection Athletes foot
Penicillium
Phytophthora infestans
Why are Fungi Important?
WWI, bacterial infections killed more soldiers than bullets.
1928 Dr. Andrew Fleming working at St. Mary’s Hospital in London noticed that mold growing on staph bacterial culture plates had killed the pathogen
zone of dead bacteria
Penicillin
Why are Fungi Important?
Penicillin kills bacteria by interfering with their ability to synthesize cell wall.
Produce antibiotics to fight off bacterial infections