Introduction to the Fungi

Lesson Plan:  Introduction to the Fungi
Time frame: 50 minutes (adaptable)
Source: http://www.clarku.edu/faculty/dhibbett/TFTOL

Preparation:
• Allow some bread (preferably multigrain with seeds and without preservatives…propionic acid is a mold inhibitor) and some fruit/vegetables to mold.  Room temperature is best, and a partly sealed container is important to retain moisture but prevent anaerobic bacteria from growing.  Don’t attempt to mold potatoes, onions or garlic.  They are highly resistant to mold growth and will usually develop foul-smelling anaerobic bacteria before mold. (A good question to students would be “Why is this?”…answer…defenses from soil fungi.)
• Collect a mixture of wild mushrooms and store-bought mushrooms.  Be cautious with wild mushrooms around children as some are deadly.  Potentially poisonous mushrooms could be displayed in a transparent container.
• If possible, obtain slides of non-mushroom fungi (such as Sordaria, yeast, Nematode-trapping fungi, etc.) as well as microscopes and slide-preparation materials.
• Familiarize yourself with the basics of fungal diversity, structure and nutrition (which you can find on the accompanying web page).
Content: (see accompanying web page…this can be made interactive as students explore)
• Fungi have diverse morphology and reproductive structures.
• There are 4 main groups of fungi, Basidiomycota, Ascomycota, Zygomycota and Chytridiomycota.
• Characteristics of each group (see web page)
• Common features of fungi (see web page)

Methods:

0:10 minutes
Gather students around collection of fungi.  Discuss several specimens and ask questions to engage students, such as:
• Where would you find this mushroom?
• What is the mushroom doing there?
• What do you think (specific structure on the mushroom) is for?
Be careful not to tell students too much in this phase.  This is your opportunity to assess their background and incite their curiosity.

10:25 minutes
Allow students to explore different fungi microscopically and macroscopically.  Give them the following task:
• Try to put fungi into groups based on their similarities (they should physically group the specimens)
Encourage use of microscope, and cutting of mushrooms.
Choose students to present their opinions.

25:40 minutes
Deliver content on 4 groups of fungi (through prepared lecture, overheads, website, constructivist approaches, etc.) and how to read the phylogram (tree that shows the evolutionary relationship among the 4 groups).  The key is that the more closely related members have fewer branching points separating them.  Could divert to brief evolution discussion.
Summative question:  What group is most distantly related to basidiomycetes and why? (Probe for morphological arguments and reference to the tree.  Where does the tree come from anyway?)

40:50 Investigating more deeply:
Compare basidia and asci (ex: using slides, overheads, making slides of mushroom gills and asci, internet search, etc.)
Relate findings to the phylogram and different shapes of the button mushroom (basidiomycete) and the morel (ascomycete), for instance.

Assessment:

Elementary:
Draw a mushroom and label cap, gills, spores and stipe.
Middle students:
Handout with thought questions:
• Why do all fungi make spores?
• What are mushrooms for?
• What are the main groups of fungi?….etc., for example
Advanced students:
Write a page with diagrams about the way spore generation and dispersal has evolved differently in the four groups (will require textbook, and/or internet/library work, but this information is easy to find.)

©2005 AFTOL