5.2: Procedure

Principles of Biology II (Lab Manual) [BIS 151] · LibreTexts

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    Part I: Fungal Ecology

    Mycorrhizae

    1. Obtain a prepared slide of ectotrophic (ectomycorrhiza) mycorrhiza. View the slide first at low power (with the 10x objective lens) before increasing the magnification to high power (with the 40x objective lens). Provide a sketch and description of your observations in the space provided. Look for the fungal hyphae wrapped around the pine root. Be sure to label both the fungi and the plant root.
    2. Obtain a prepared slide of endotrophic mycorrhiza (arbuscular mycorrhizae). View the slide first at low power (with the 10x objective lens) before increasing the magnification to high power (with the 40x objective lens). Provide a sketch and description of your observations in the space provided. Look for the fungal hyphae tightly coiled withing the plant cells of the root. Be sure to label both the fungi and the plant root.

    Lichens

    1. Obtain a prepared slide of lichen. View the slide first at low power (with the 10x objective lens) before increasing the magnification to high power (with the 40x objective lens). Provide a sketch and description of your observations in the space provided. Look for the fungal hyphae surrounding the large algal cells. Be sure to label both the fungi and the algae.

       

    Part II: Fungal Diversity

    Zygomycota

    1. Obtain a prepared slide of Rhizopus fungi. View the slide first at low power (with the 10x objective lens) before increasing the magnification to high power (with the 40x objective lens). Provide a sketch and description of your observations in the space provided. Note that there are two regions of the slide, one which contains zygosporangia and one that contains the sporangiophores. Provide a sketch and description of your observations in the space provided. Be sure to label both types of spores as well as the hyphae. Indicate whether the hyphae is septate or coenocytic.

    Basidiomycota

    1. Obtain a mushroom, dissecting tray and dissecting kit. Examine the different components of the mushroom, locating the stem, cap and gills. Draw a diagram of your mushroom in the space provided, making sure to label each of these structures. If the gills are not visible, remove the tissue protecting them (this is called a veil) gently with your forceps. Be careful not to touch the gills with the forceps.
    2. Grasp the cap firmly with one hand and the stem with the other hand. Gently wiggle and/or twist the stem until it breaks away from the cap. Pinch the stem between your fingers until it breaks into two or more long pieces. Use your tweezers to gently pull small pieces of the stem apart. The thin, hair-like filaments you will see where you split the stem are the hyphae. Prepare a slide of the hyphae by placing the small stem fragment on a glass slide and adding a drop of water and a cover slip. View the slide first at low power (with the 10x objective lens) before increasing the magnification to high power (with the 40x objective lens). Provide a sketch and description of your observations in the space provided. Be sure to note whether the hyphae you observe is septate or coenocytic.
    3. Place the stem pieces on a corner of your paper towel and turn your attention to the cap. Look at the underside of the cap to study the gills. Each gill is lined with thousands of small structures called basidia. Using your forceps, gently remove one gill from the cap. You will get better results if you GENTLY grasp the gill near where it attaches to the cap. Try to avoid touching the free edge, the one along the bottom of the gill, with your forceps. The basidia you want to see under the microscope are fragile and easily damaged if you are not careful. Place the gill on a microscope slide. Add a drop of water and a coverslip and then place your slide on the microscope and examine the gill using the 10x lens. Look at the edge of the gill that was not attached to the mushroom and look for the little finger-like projections. Switch the microscope to the high power/40x objective lens. Look at the finger- like projections under high power. These are the basidia. If your mushroom is mature the basidia may have spores attached to them. Provide a sketch and description of your observations in the space provided. Be sure to label the gills, basidia and spores.

    Ascomycota

    1. Prepare a wet mount of yeast by adding a drop of the liquid yeast culture to a slide and adding a coverslip. View the slide first at low power (with the 10x objective lens) before increasing the magnification to high power (with the 40x objective lens). Provide a sketch and description of your observations in the space provided. Scan the slide to look for examples of budding, if present sketch and label the parent and daughter cell.
      Note

      Alternatively, if you are provided with an agar culture of yeast, you should add a drop of water to a clean slide. Using a sterile loop, you can then collect a small sample of yeast by gently touching the loop to the growth on the agar plate. Gently swirl the loop into the drop of water to disperse the yeast. Lastly, add a cover slip.

    2. Obtain a slide of Sordaria fungi. View the slide first at low power (with the 10x objective lens) before increasing the magnification to high power (with the 40x objective lens). Provide a sketch and description of your observations in the space provided. Be sure to label both the ascus and the ascospores.
    3. Obtain a slide of Penicillium fungi. View the slide first at low power (with the 10x objective lens) before increasing the magnification to high power (with the 40x objective lens). Provide a sketch and description of your observations in the space provided. Be sure to label both the condiophores and the conidia.

       

    Part II: Settle Plate Method

    1. Obtain 3 Sabouraud or potato dextrose agar plates. Label the bottom of the plates (not the lid) with your group/group members name and the date. You want to label the plastic dish, not the agar itself. Additionally, one plate will be labeled “classroom”, one will be labeled “hallway” and the other will be labeled as “outside”.
    2. Place these plates in their respective locations with the lids removed and the agar exposed for a total of 30 minutes.
    3. At the end of the 30 minutes, replace the lids and bring the plates to the classroom for incubation. You will observe the growth patterns of the plates in the lab next week.
    4. After the plates have incubated for a week, sketch and describe the observed growth patterns on each plate below. First, examine the plates by simply looking at them with your unaided eyes. You can also use the dissecting microscope/stereoscope to observe the growth patterns on each plate. Remember to use both the zoom knob (to change the magnification) and the focus knob to get a clear image of what you are seeing.
      Caution
      • Often, you will find moisture or condensation inside the lid which may make it difficult to clearly see some regions of the plate. It may be tempting to open the plate and remove this moisture. However, the lids will be sealed with tape, be sure to leave the tape intact and never remove the lid during your observations, doing so will release mold spores into the air.
      • Once you have completed your observations, the used fungal plates should be placed in the biohazard container for proper disposal.

    This page titled 5.2: Procedure was last modified on Tue, 09 Dec 2025 17:47:24 GMT and is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Beth Cliffel.