Observing Monerans, Protists and Fungi

A. Monerans
1. Place three or four beans in 100 mL of water and let stand for 4-5 days to grow a rich bacterial culture.
2. Bacteria can be viewed more easily if they are fixed and stained. Fixing means killing the cells and fastening them to the slide. They are stained by soaking them in a staining solution. To fix the bacteria, place a drop of the culture on a slide, hold the slide with the smear upward and pass quickly and repeatedly through a bunsen burner flame until the smear is dried.
3. Place a drop of crystal violet stain on the smear and let stand for 30 seconds. Rinse the slide gently in a beaker of water.
4. Observe and make a detailed drawing of as many types of bacteria as you can.

B. Protists
1. Prepare a protist culture by adding the dried protists mixture to 100 mL water in a small culture dish. Do not shake or stir the mixture. Some particles will sink while some will float. Incubate at 20-22 oC for 4-5 days. Be sure to check the culture daily and replace any water that evaporates.
2. Using a depression slide, make a wet mount of the protist culture.
3. Prepare detailed drawings of a few protists. Use the guide to identify them if you can. You can fix and stain them if you like. Also, you can slow the movement of the protists by adding a drop of methyl cellulose.

C. Fungi
1. Cover the bottom of three separate petri dishes with damp paper towel. Place a few grains of rice in one, a few small (1 cm x 0.5 cm) pieces of potato in another, and a few small pieces of bread in the third. Cover the dish and seal it with tape to prevent drying out. Place the culture in a cool, dark location for 4-5 days.
2. Obtain a sample of bread mold from your culture and prepare a wet mount. Make a detailed drawing showing both the hyphae and sporangia. You should be able to locate spores, cell walls and nuclei.
3. Do the same for the fungus growing on potato and rice.