Characteristics

• Phylogenetics along with the presence of compounds like chitin and glycogen make fungi more closely related to animals than plants
• Fungi are generally saprobrophytic heterophiles, like bacteria. Saprobes secrete enzymes and absorb nutrients rather than ingesting food. They are important in the breakdown of organic matter.
• Basic unit is hyphae - filamentous strands (except yeasts which tend to be unicellular)
• Septa are partial cell walls that seperate cells in the haphae. Some fungi are non-septate (like one long cell with lots of nuclei).
• A collection of interwoven hyphae form the fungal body called mycelium
• Hyphae can be of 2 mating types : + and - (both haploid)
• When not undergoing sexual reproduction, hyphae are haploid (n)
• When + and - hyphae fuse, they exist for some period of time with two nuclei (dikaryotic). These may quickly fuse to produce a diploid (2n) cell that then undergoes meiosis to produce haploid spores. In other species hyphae can be dikaryotic for years before fusion occurs to produce a sexual spore producing structure.
• Spores can be produced both sexually and asexually. They are usuall windblown. Some mushrooms can produce millions of spores per hour.
• Some species can multilply by budding (yeasts) or by hyphae fragmentation (lichens)
• Phyla are based on the reproductive structures.

Zygomycota - Zyogspores

• Black bread mold (Rhizopus stolonifer) is an example
• Fusion of + an - cells causes production of a crusty diploid (2n) zyogopore. Meiosis occurs and a sporangium arises to produce haploid spores
• Sporangium are also produces asexually (both structures are call sporangium)
• Look at our slides and be able to recognize the major structures - zygospores, stolens, rhizoids.

Ascomycota - Sac Fungi

• Examples include morels, truffles, yeasts, molds (like Penicillium and Neurospora)
• Fruiting body is called an ascocarp. Shape of ascocarp divides this group further, like the Cup fungi that have cup shaped ascocarps
• Fertilization followed by meiosis results in 8 haploid spores inside inside a sack called an ascus. An ascocarp may contain many of these. Some, like yeasts, don't really produce an ascocarp.
• Asexual spores may be produced in structures called Conidia and their spores are called conidiospores
• Look at yeasts (budding); Peziza (ascus, ascospores, ascocarp); and Aspergillus (conidia and conidiospores)

Basidiomycota - Club fungi

• Mushrooms, Toadstools, Puffballs, Smuts, and Rusts
• Sexual spores (basidiospores are produces in club shaped basidia
• The fruiting body is called a basidiocarp. You see a big fungus, it's probably a Club fungus. Some are yummy (shitaki and portabellas), others not so much (you'll die)
• These guys may have dikaryotic hyphae for years.
• Fairy rings are cool.
• Lots of samples in the lab. Look at slides of Coprinus to see basidia and basidiospores.

Lichens

• A fungus (usually Ascomycetes) associated with a unicellular photosynthesizer (usually a cyanobacteria but could be a eukaryotic alga)
• Reproduce by fragmentation since it needs to contain two different species.
• A relationship of this kind is called Symbiosis
• Sybiosis can be mutually beneficial (Mutualism) or Parasitic - where one benefits and the other is harmed.
• The long held idea that lichens are mutualistic has been challenged. Some believe that the fungi are parasitic on the alga.

Mycorrhizae

• Form mutualistic relationship with the roots of plants.
• They greatly increase the absorptive ability of plants to get water and minerals.
• Plants provide them with organic nutrients such as sugar.
• They are Everywhere.

PSTCC Practical Review

A study guide before each practical will be sent via email to you from Bio1120's master teacher, Linda Smith-Stanton. Here are the items she thinks you should be familiar with:
• General characteristics of fungi (uni or multicellular, auto or heterotrophic...). Know what a fruiting body is.
• The fungal division that Rhizopus (black bread mold) represents.
• The appearance of the Rhizopus sporangia - fig 15.2 and #4 left pic on p.198.
• What the zygospores of Zygotmycota look like - fig 15.2 and #4 right pic on p.198.
• What phases of the Zygomycota's life cycle are diploid (fig 15.2)
• Identification of and info about the budding of yeast.
• The appearance of ascospores in asci. See fig 15.3.
• The appearance of condiospores and whether they?re sexual or asexual spores made by Aspergillus.
• Representatives of the fungal division Basidiomycota - mushrooms, puffballs, shelf fungi and rusts (there may also be pictures of these in your textbook ch. 24).
• The appearance of basidia and the basidiospores - fig 15.4 (low center).
• Identification of mushroom structures - stalk, annulus, cap, gills, basidia and basidiospore locations.
• Lichens and what organisms comprise a lichen.
• The identification of the fungal vs the algal components of a lichen (fig 15.5a).