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.
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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?
Study Guide
Name at least two synapomorphies that are common between fungi and animals: what traits make fungi more closely related to animals vs. plants? Review: 'synapomorphy' definition: a trait present in an ancestral line of organisms, that is then shared by all the evolutionary descendants of that line; or the presence in 2+ different organisms of the same characteristic (even in a modified form) which share that trait because it originated from their common ancestor
- What is remarkable about fungal habitats? Are they live, dead, or both?
- Are most fungi single-cells or are most fungi multicellular? Name two single-celled fungi.
- What makes the cell walls of fungal cells different from plant cell walls?
- What is chitin? What are the building blocks?
- What is ergosterol, where is it found, what does it do, and why is it medically important?
- What are mycelia? What are haustoria; why are they different than other mycelia? Name a fungi with haustoria.
- Describe the two different types of hyphae - based on how the cells are organized.
- What is are the biological purposes of hyphae, meaning to what advantage, or why would an organism evolve to have them?
- Are fungi sexual or asexual or both?
- What’s the difference between 'fungi' and yeasts?
- Are spores haploid or diploid, what is karyogamy, what does 'dikaryon' mean?
- Does mitosis occur in sexual or asexual plant growth? Tricky: look at slide life cycles.
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What are the six (6) main groups of fungi?
- a. Name one distinguishing characteristic of each, setting them apart from other groups
- b. Name at least one example fungus in each group - where does it grow?
- Why are microsporidia an “outgroup”? What synapomorphy makes them different.
- Where are chytrids found?
- How are chytrids affecting amphibians?
- What is interesting about a zygosporangium structure? Is it haploid or diploid?
- What is the defining feature of an ascomycete fungus? Name three common ascomycetes?
- Are ascomycete fungi haploid or diploid?
- How do fungi make ants crazy (watch video)?
- Why do leaf cutter ants ‘farm’ fungi?
- What is unique about basidiomycetes? Name four common basidiomycetes.
- Why are fairy rings shaped like that? Why aren’t there clubs or fruiting bodies in the center of the ring?
- What is the evidence that ancient fungi existed?
- Why are fungi critical to the carbon cycle? What do they breakdown, what do they produce/create?
Vocabulary
- Heterotroph
- Chemoheterotroph
- Saprophyte
- Symbiosis
- Mutialism
- Parasite
- Hyphae
- Septa
- Coenocytic
- Haustoria
- Mycelia
- Arbuscular
- Micorrhizae
- Soredia
- Mushroom vs. fruiting body
- Thrush
- Dikaryon
- Plasmogamy
- Karyogamy
- Spore
- Sporangia
- Conidia
- Zygote
- Ascus