Ken-A-Vision Experiment 2
A UNIVERSE IN A DROP OF WATER:
Objectives: To better understand how to gather samples and to observe living protozoan and other simple organisms.
NOTES TO THE TEACHER:
1. The best all-around environment for collecting live protozoan or one-celled animals is from unpolluted ponds or lakes containing fish. Collect by using clean jars or pipettes from various levels and locations without agitating the water.
2. To maintain the protozoans collected, place a handful or hay (Timothy is preferable) in a jar then fill ¾ full with pond water. Set aside without a lid exposing the sample to moderate temperature only and away from direct sunlight.
3. Algae can also be collected from stagnant pools. Look for green "scum" floating on the surface.
4. Most living organisms when exposed to the intense light and heat of a microscope try to flee.
So, in order to observe quick moving microscopic specimens you can:
5. Have students use the low power objective to find specimens then slowly work up to hight power.
6. Live specimens can be purchased from most science supply companies at minimal expense. Some of the most common organisms used are: ameba, paramecium, Euglena, spirogyra, volvox, and hydra.
7. Commercially prepared slides are not as exciting as live samples, but provide an easy way to introduce any student to observing microscopic organisms. Ken-A-Vision would be a possible source for such slides.
8. Dichotomous keys used to identify various organisms can be purchased through science supply houses, checked out from school libraries, borrowed from experts, ordered through any local book store, or found in biology textbooks.
1. Encouraging students to research individual interests might lead to a science fair project.
2. Invite experts into the classroom to speak about such things as protozoan parasites, how these organisms are indicators of pollution and water quality, or a general information lecture or demonstration.
3. Have the students construct a simple classification system of microscopic animals based upon their differences on such characteristics as motility, shape, number of cells, or color. These classification activities can be expanded to include other living organisms.
4. It is easy to study the effects of chemical on protozoans by using such solutions of ink, vinegar, baking soda, salt, or sugar.
Activity: THE WORLD DOWN UNDER! or YOUR IDDY BIDDY BUDDIES!
Purpose: Observing simple organisms found in pond water
a. How do the different organisms move?