Kingdom Fungi Fungi Kingdom contains: • • • • • Molds Mildews Rusts & Smuts Yeasts Mushrooms Ecological Roles • Decomposers • Parasites • Mutualistic symbionts Trophic Level • Saprophytic • Parasitic Indian Pipe is saprophytic Fungal Roles • Break down organic material returning nutrients to the soil. • Yeasts are useful in the making of bread and fermented drinks. • Human pathogens e.g. athlete's foot and ringworm. External Digestion Extra-cellular digestion occurs by secreting enzymes into environment and absorbing the nutrients produced. Fungus Structure Fungal Parts Hypha - the vegetative filament Septum - perforated cross walls Mycelium - a mat of interwoven hyphae Why aren’t fungi classified as plants? • Non-photosynthetic (Heterotrophic) • Fungi cell walls are made of chitin • • Plant cell walls are made of cellulose • Fungi store their food as glycogen (like animals) Plants and green algae store their food as starch Life Cycle Life Cycle • Begins as a spore that grows when conditions are right • Out of the spore wall grows a hypha • The body of the fungus is made up of hyphal threads collectively called the mycelium • The mycelium grows in soil or within dead wood or living organisms • When growing conditions are favorable, the mycelium develops fruiting bodies, e.g. mushrooms • Fruiting bodies produce new spores. Types of Asexual Reproduction • Forming spores at the end of the hyphae. • Fragmentation- If the hyphe are broken, the pieces will grow into complete new organisms. • Yeasts reproduce by an asexual process called budding. In this process, the yeast cell pinches itself off to produce a small offspring cell. Spores at the ends of hyphae Budding Sexual Reproduction • Each of the four divisions of fungi have different forms of sexual reproduction Fungal Classification • Chitridiomycota – Primitive flagellates • Zygomycota - Common bread mold • Basidiomycota - Mushrooms, puffballs, rusts, smuts, and stinkhorns • Ascomycota- Mildews, yeasts, and truffles (sac fungi) • Deuteromycota – Ringworm, athletes foot Fungi Cladogram Chitridiomycota • Most primitive group • Aquatic parasites (may be responsible for global decline in amphibians) • Only Fungi with flagella Zygomycota • Hyphae lack septa • Asexual reproduction is by conjugation Basidiomycota • Underground hyphae intertwine and grow upward to produce a mushroom. • A "fairy ring" is actually a single organism. As the hyphae expand outward, the mushrooms grow around the outer edge. As long as the organism survives, the circle of mushrooms will be wider every year. Fairy Ring Stinkhorns Puffballs Smuts Rusts Rust Pathogenesis Mushrooms Mushrooms Mushroom Life Cycle Gills Ascomycota • Largest group of fungi • Named for the reproductive sacs or Asci that form near the tips of the hyphae. • Ascospores are formed here and released into the air when the ascus ruptures. • These spores germinate to form new hyphae. Mildew Truffles Yeast Candida albicans Deuteromycota Tinea Pedis Tinea corporis onychomycosis Fungal Symbiosis • Over 90% of plants have fungi associated with their roots. • The fungus absorbs and concentrates phosphates for delivery to the plant roots. • In return, the fungus receives sugars synthesized by the plant during photosynthesis. Lichens • A symbiotic association between a fungus and a photosynthetic partner, usually green algae. • The fungi hyphae provide protection and hold moisture while the photosynthetic partner provides food. Lichens • Green color is because of the green algae cells growing between the hyphae of the fungus. • The grey is a lichen • The orange is a fungus without algae Lichen