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KEY CONCEPT Fungi are saprobes (decomposers). 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.
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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
Fungi are multicellular organisms, with the exception of yeasts. • hyphae • mycellium • fruiting body
Sac Fungi (Ascomycota) • Examples • Yeasts are single-celled. • Morels and truffles are multicellular. • Form a reproductive sac, called an ascus.
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
include mushrooms, puffballs, and shelf fungi • reproductive structures called basidia • Club fungi (Basidiomycota).
Group of fungi that produces asexually but sexual form is unknown Examples: leaf spot fungus, Penicillium, Aspergillus Imperfect Fungi (Deuteromycota)
Fungi reproduce sexually and asexually. • Most fungi reproduce both sexually and asexually. • Yeasts reproduce asexually through budding. • Yeasts form asci during sexual reproduction.
Multicellular fungi have complex reproductive cycles. • distinctive reproductive structures • Basidiomycota have basidia • Zygomycota have zygospores • Ascomycota have asci
Alternation of Generations- part of reproductive cycle is asexual, part is sexual.
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
A few fungi always cause disease Some are normally harmless, but can grow out of control under right conditions Fungi as pathogens Yeast can overgrow in presence of antibiotic
Yeast infections from antibiotic use Ringworm Athlete’s foot Human Diseases
Dutch elm disease • Dutch elm disease • Peach scab • Gray mold • Plant Diseases Elm bark beetle Gray mold
Mutualistic Fungi • Symbiotic relationship with another organism • Both organisms benefit
Fungi and algae Fungi protect the algae Algae performs photosynthesis Lichens
Fungi and plant roots Fungi absorb nutrients and water Plant provides glucose from photosynthesis Mycorrhizae Cross Section of root →
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!
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