In BIMS 1101 Unicellular Organisms Lab, Dr. Benoit takes students through an amazing tour of the unseen world, one filled with bacteria and protozoa and algae and yeast. The course teaches basic cell biology and the diversity that exists among the smallest forms of life. As a way of demonstrating the metabolic diversity of bacteria, all students create Winogradsky columns by filling Falcon flasks with diatomaceous earth, a variety of chemicals, and some water drawn from pond sludge (see photo). These are the students’ pets, cared for and tended to by the students. Dr. B encourages students to drop by the lab regularly to visit their pets and to enjoy their journey to maturation. At the end of the semester, students are free to take them home where they can continue to mature and change for many years.
The preparation begins white usually, but chemical changes caused by a variety of bacterial turn the many minerals present into a technicolor show. A good balance of chemicals and diversity of bacteria can result in reds and greens and blacks and yellows and purples as one species of bacteria after another transforms the minerals into colorful compounds. It is the microbial equivalent of a garden filled with diverse plants.
As educational as the Winogradsky column is, the fun take on the project by Dr. Benoit demonstrates an important component of science at McMurry – if it isn’t fun, something is wrong!