Mushrooms are fungal fruiting bodies.
Fungi are more closely related to animals than plants.
Single-celled fungi are generally called yeast.
Multi-cellular fungi are generally called mold.
Overview
- Fungi
- Are heterotrophs, get their food externally.
- Saprophytes
- Chemically absorb their food via extracellular digestion.
- Yeast
- Single-celled fungi.
- Fungal cell walls are strengthened by chitin polysaccharides (glucose).
- Fungi have cell walls & cell membranes.
Table 1: A fungus is not a plant
| Fungus | Animal | Plant | |
|---|---|---|---|
| Chitin | yes | yes | no |
| Food storage | glycogen | glycogen | starch |
Phylogeny
- Ophisthokonts
- Outgroup of animals and fungi.
- Microsporidia
- Outgroup for fungi.
- Unicellular
- No true mitochondria.
- Intracellular parasite of animals.
Phyla of Fungi
- Chytids
- Some chytids produce flagellated male and female gametes from a multicellular haploid stage.
- Female gamete vs. male gamete in fungi?
- Zygomycetes Zygomycota
- Remain dormant for months during harsh conditions.
- Glomeromycete Fungi
- Micorrhizae, symbiotic w/ vascular plant roots and fungi.
- Fungi in plant root systems.
- Ascomycetes Sac fungi
- Sexual, haploids mating.
- Penicillin is harvested from fungi, kills bacteria by interfering w/ bacterial wall synthesis.
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Zombie Ant Fungus is an ascomycete cordyceps.
- Basidiomycetes Classic mushrooms
- Often psychedelic/poisonous.
-
Fairy ring, expanding group of fungi expands outward in a circle after it consumes inner nutrients.
- Saprophytic Fungi & bacteria
- Are major decomposers of organic matter (cellulose, lignin, & keratin).
- Haustoria
- Branchings that push through cell wall & membrane to harvest nutrients from hosts.
- Lichen
- Fungi + photosynthetic microorganism live in a symbiotic relationship.
- Lichens reproduce by soredium, broken off parts that form new colonies.
Parts of Fungi
If fungi have flagellum for sexual reproduction, the flagellum is single and posterior on gametes.
- Fruiting Bodies
- Sex organs
- Mushrooms
- Spores
- Fungal equivalent of seeds.
- Fungal spores are haploid, one copy of genome.
- Mycelium
- The "body" of a multicellular fungus can either be septate or coenocytic.
- Composed of hyphae.
- Mycelia
- Interwoven filaments of hyphae.
- Septate
- ?
- Coenocytic
- ?
- Ergosterol
- Needed for plasma membranes in fungi.
Reproduction
- Reproduction of Fungi
- Mostly asexual, some sexual.
- Spores (n) germinate into haploid offspring.
- Most fungi spend most of their life in a haploid state, reproducing asexually.
- Fungal spores are haploid. Germinate into haploid offspring.
- Chytrid fungi affect amphibians.
- Add mycorrizae to hydroponics plant roots?