Presentation on theme: "22-1 Characteristics of Fungi"— Presentation transcript:
122-1 Characteristics of Fungi 22-2 Fungal Diversity22-3 Fungal Associations
2Fungi KingdomFungi are heterotrophic – the stalk and the cap of a mushroom are not green like the leaves of a plant; plants appear green because they contain chlorophyll; fungi do not contain chlorophyll; fungi obtain energy by absorbing organic molecules from their surroundings
3Fungi KingdomFungi have filamentous bodies – the long slender filaments weave tightly together to form the fungus body and reproductive structuresA giant fungus of the species Armillaria ostoyae in the Malheur National Forest in Oregon was found to span 8.9 km² (2,200 acres), which would make it the largest organism by area.
4Fungi KingdomFungal cells contain chitin – cells of all fungi have walls made of chitin (the tough material found in the exoskeleton of insects and other arthropods)
5Fungi KingdomFungi have nuclear mitosis – in plants/animals the nuclear envelope disintegrates during mitosis; in mushrooms the nuclear membrane remains intact and mitosis is complete when the nuclear membrane pinches in two
6Fungi Structure Hyphae – slender filaments that make up fungi bodies Mycelium – tangled mass of hyphae
7Fungi are Heterotrophic Fungi digest food outside their bodiesHyphae tips secrete powerful digestive enzymes that break down organic matter
8Fungi are DecomposersIn their search of food, many fungi attack nonliving organic matter and decompose these materials.Other fungi absorb nutrients from living hosts, which sometimes become weakened and succumb to infection or disease.
9Fungi Reproduction Fungi reproduce by releasing spores. Spores form in reproductive structures (basidia) at the tips of hyphae.Reproductive structures (mushrooms) extend high above the food source so that air currents can carry the spores to a new habitat.When a spore lands in a suitable place, it begins to divide and soon gives rise to a new fungal hypha.
11SPORESSpores are usually haploid and unicellular and are produced by meiosis in the sporophyte.a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions.A chief difference between spores and seeds as dispersal units is that spores have very little stored food resources compared with seeds.Once conditions are favorable, the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte.
12Phyla of Fungi Zygomycota: black bread molds Ascomycota: morels, truffles, yeasts, cup fungiBasidiomycota: mushrooms, puffballs, rusts, smutsDeuteromycota (Fungi Imperfecti - sexual reproduction has not been observed): Penicillium, athletes foot, ringworm, blue cheese mold
14Fungal AssociationsLichen – symbiotic association between a fungus and a photosynthetic partner in which the fungal partner protects the photosyntheticMycorrhizae – symbiotic association in which a fungus transfers minerals to a plant’s roots, which in turn supply carbohydrates to the fungus