Swope's+Lesson+Plans+&+Reports

=**Protist Diversity**=

Time: Early August

Targeted Student Group: Freshmen Biology Students

Materials:
 * compound light microscopes
 * collection bottles
 * water samplers
 * microscope slides
 * cover slips
 * pipettes or droppers

Goals:
 * Experience and appreciate the unique opportunity the Nature Center offers students of biology.
 * Practice safe, sustainable and ethical wildlife habitat and organism collection techniques.
 * Evaluate the diversity of protists and algae in a sample of running creek water.
 * Evaluate the diversity of protists and algae in a sample of stagnant water.
 * Differentiate between the two samples.
 * Describe observations in a written and in a sketch format.
 * Compare protist populations before and after preparation of a hay infusion.

Procedure:
 * Explain elementary safety precautions regarding hazardous plants and animals in the outdoor setting before taking students outside.
 * Discuss safe, sustainable and ethical sampling techniques with students while they are outside seated in the outdoor classroom lecture area.
 * Send students to collect samples (80-100mL each) of running and stagnant water.
 * Return to the classroom.
 * Lecture on the basic operation of a compound light microscope.
 * Prepare wet mount slides of each of the samples and examine them for the presence, variety and concentration of protists and algae. Lots of oooh and ahhh time here.
 * Help students differentiate between biotic and abiotic artifacts in their samples.
 * Prepare a sketch of a rich portion of the sample under low, medium and high power.
 * Discuss the possibly low protist quantity and brainstorm why it is low.
 * Introduce the food web of protists.
 * Prepare a hay infusion as follows:
 * Find some hay, dead grass, or other dry vegetation.
 * Place the vegetation in the sample jar with the original pond water. It should not pack it tightly; 25% full of hay should be sufficient.
 * Place the lid on it and make it air tight. Petroleum jelly may help.
 * Let it sit at room temperature for a few days. I recommend placing it in a fume hood.
 * As the hay decomposes, the sugars in it cause an enormous population explosion among the bacteria that are present. These in turn provide a rich source of nutrition for the protists, enabling them to breed rapidly.
 * Revisit the samples after a few days and compare the protist quantity and diversity with the original samples.