Chapter 20: The Fungi

Most Fungi have Filamentous Bodies: Chapter 20: Fungi Most Fungi have Filamentous Bodies: Mycelium: Interwoven mass of threadlike filaments (hyphae) Septa: Partitions separating elongated cells of hyphae (Figure 20.1) Contain cell walls composed of chitin Mushroom: Reproductive structure of certain fungi

Fungi Obtain Nutrients from Other Organisms (Heterotrophs): Chapter 20: Fungi Fungi Obtain Nutrients from Other Organisms (Heterotrophs): Saprobes: Obtain nutrients from dead organisms (decomposers) Parasites; symbionts; predators Digestion / Absorption occurs outside the body Fungi Reproduce both Sexually & Asexually: 1) Asexual (normal conditions): Mycelium breaks off pieces Spores: Tiny, lightweight reproductive packages Haploid (single copy of each chromosome) 2) Sexual (stressful conditions): Hyphae fuse: exchange genetic material Release spores (mixed DNA) Fungi Classified Based on Sexual Structures

1) Chytrids (Chytrodiomycota) Classification of Fungi: Chapter 20: Fungi 1) Chytrids (Chytrodiomycota) Classification of Fungi: Aquatic; produce swimming spores Ancient group Saprobic, parasitic 2) Zygote Fungi (Zygomycota) Inhabit soils & decaying plants / animals (e.g. bread mold) Sporangia: Asexual reproductive structure housing spores Zygospore: Sexual reproductive structure (tough & resilient)

3) Sac Fungi (Ascomycota) Classification of Fungi: Chapter 20: Fungi Classification of Fungi: Saprobic (e.g. morels) ; parasitic (e.g. dutch elm disease) Medical Fact: Producer of penicillin Ascus: Sexual reproductive structure containing spores 4) Club Fungi (Basidiomycota) Saprobic (e.g. mushrooms); parasitic (e.g. rusts / smuts) Basidia: Sexual reproductive cells (club-shaped) which give rise to spores

Classification of Fungi: 5) Imperfect Fungi (Deuteromycota) Chapter 20: Fungi Classification of Fungi: 5) Imperfect Fungi (Deuteromycota) Sexual reproduction never observed (can’t classify) Some Fungi Form Symbiotic Relationships: A) Lichen: Association between fungi (ascomycota) and protists (green algae) or bacteria (cyanobacteria) Mutualistic Interaction: Fungus = Shelter / Protection Symbiont = Food production Primary Succession Pioneer

Some Fungi Form Symbiotic Relationships: Chapter 20: Fungi Some Fungi Form Symbiotic Relationships: A) Lichen B) Mycorrhizae: Association between fungi (all groups) and plant roots (most plants) Mutualistic Interaction: Fungus = Digests / Absorbs Nutrients Plant = Food production May allow for communication among plants... May have aided plant’s invasion of land...

Rusts / Smuts (Basidiomycota) Fungal / Human Interactions: Chapter 20: Fungi Fungal / Human Interactions: A) Fungi cause the majority of plant diseases: Dutch Elm Disease (Ascomycota) B) Fungi are used to control pest species C) Fungi cause human diseases: Athlete’s foot / Ringworm (Ascomycota) D) Fungi produces toxins: Ergot: Rye plant infection (Ascomycota) LSD - Hallucinogen derived from an ergot Might have been responsible for Salem Witch Trials

Antibiotics (e.g. penicillin) Fungal / Human Interactions: Chapter 20: Fungi Antibiotics (e.g. penicillin) Fungal / Human Interactions: E) Fungi treat diseases: Cyclosporin (organ transplants) F) Fungi are good eatin’: Edible mushrooms (know what you eat!) Cheeses (e.g. Gorgonzola - ascomycota mold) Yeasts (single-celled ascomycota)

Truffle: Symbiotic relationship between fungus & oak tree Chapter 20: Fungi Truffle: Symbiotic relationship between fungus & oak tree Ascomycota Fungal Ingenuity: 1) Odors used to disperse spores: 2) Shotgun approach to dispersal: Pilobolus: Spore cases are shot from reproductive structure Zygoomycota 3) Fungi of the wild west / high seas: Some fungi produce specialized hyphae to harpoon / snare nematode prey

A) Protists (single-celled eukaryotes) Chapter 18: Systematics The Prokaryotes: 1) Bacteria 2) Archaea Domains 3) Eukarya: A) Protists (single-celled eukaryotes) B) Fungi (multicellular; absorptive digestion) Kingdoms C) Plantae (Multicellular; photosynthsis) D) Animalia (Multicellular; ingestion)