Presentation on theme: "19.5 Diversity of Fungi KEY CONCEPT Fungi are saprobes (decomposers)"— Presentation transcript:
19.5 Diversity of Fungi KEY CONCEPT Fungi are saprobes (decomposers)
19.5 Diversity of Fungi Plants and Fungi have similar and dissimilar traits Plants: photosynthesis; true roots, stems, and leaves; cell walls with cellulose Plants and Fungi: non-moving, produce spores Fungi: absorb food with hyphae; cell walls with chitin
19.5 Diversity of Fungi Fungi are multicellular organisms, with the exception of yeasts. – hyphae – mycellium – fruiting body
19.5 Diversity of Fungi Septate and Coenocytic hyphae
19.5 Diversity of Fungi Sac Fungi (Ascomycota) Examples –Yeasts are single-celled. –Morels and truffles are multicellular. Form a reproductive sac, called an ascus.
19.5 Diversity of Fungi Bread mold Zygomycota ("Conjugation Fungi") –Molds that are often found on spoiled food including: bread, cheese and meat. –Mycorrhizae belong to this group –Form zygospores during reproduction
19.5 Diversity of Fungi Club fungi (Basidiomycota). – include mushrooms, puffballs, and shelf fungi –reproductive structures called basidia
19.5 Diversity of Fungi Imperfect Fungi (Deuteromycota) Group of fungi that produces asexually but sexual form is unknown Examples: leaf spot fungus, Penicillium, Aspergillus
19.5 Diversity of Fungi Fungi reproduce sexually and asexually. Most fungi reproduce both sexually and asexually. –Yeasts reproduce asexually through budding. –Yeasts form asci during sexual reproduction.
19.5 Diversity of Fungi Multicellular fungi have complex reproductive cycles. – distinctive reproductive structures –Basidiomycota have basidia –Zygomycota have zygospores –Ascomycota have asci
19.5 Diversity of Fungi Alternation of Generations- part of reproductive cycle is asexual, part is sexual.
19.5 Diversity of Fungi All fungi form spores and zygotes.
19.5 Diversity of Fungi Fungi have + and – hyphae instead of male and female.
19.5 Diversity of Fungi KEY CONCEPT Fungi recycle nutrients in the environment.
19.5 Diversity of Fungi Fungi and bacteria are the main decomposers in any ecosystem. –decompose dead leaves, twigs, logs, and animals –return nutrients (carbon, nitrogen and minerals) to the soil –absorb food quickly and recycle nutrients quickly
19.5 Diversity of Fungi Fungi as pathogens A few fungi always cause disease Some are normally harmless, but can grow out of control under right conditions Yeast can overgrow in presence of antibiotic
19.5 Diversity of Fungi Human Diseases Yeast infections from antibiotic use Ringworm Athlete’s foot
19.5 Diversity of Fungi Plant Diseases –Dutch elm disease –Peach scab –Gray mold Elm bark beetle Gray mold Dutch elm disease
19.5 Diversity of Fungi Mutualistic Fungi –Symbiotic relationship with another organism –Both organisms benefit
19.5 Diversity of Fungi Lichens Fungi and algae –Fungi protect the algae –Algae performs photosynthesis
19.5 Diversity of Fungi Mycorrhizae –Fungi and plant roots -Fungi absorb nutrients and water -Plant provides glucose from photosynthesis Cross Section of root →
19.5 Diversity of Fungi Fungi and some insects form symbiotic relationships Leaf cutter ants build piles of leaves and add fungus. Fungus breaks down leaves and ants eat the mycelium!
19.5 Diversity of Fungi Fungi are studied for many purposes. Fungi are useful in several ways. –as food – as antibiotics – as model systems for molecular biology (eukaryote cells) Penicillum