WASH YOUR HANDS - - - a lesson from Mr. Creamer's Biology Classes

 

Students in Mr. Creamer’s SEI Biology classes study the different types of cells. Bacteria, which are prokaryotes, can be hard to see without sophisticated and expensive microscopes, so students cultured bacteria to see what bacteria we come into contact with on a daily basis. Students researched the recipe for making the agar, the gelatin-like substance that fills the plate and calculated the measurements for making the estimated plates needed to cover the school. Students visited the school’s water fountains, door handles, desks, lunch tables, and floors to collect samples. We compared these samples to a control plate, where no bacteria was collected, and to an experimental sample from the bathrooms. After incubation, results are always surprising. Students predicted that the bathrooms would yield the highest amount of colonies, but because the bathrooms are cleaned thoroughly and regularly by our wonderful custodial staff, the bathroom plate yielded negligible colonies! Students are always intrigued by the fact that water fountains have more colonies of bacteria than do bathrooms. The floor and places where we touch with our hands (door handles, water fountains, desks, and tables) understandably yielded a variety of colorful colonies. The winner of last year’s highest colony winner, Principal Constantino’s old office door handle, was beat out by this year’s winner: the first floor stairwell, where hundreds of students touch each day! Lesson learned: always wash your hands, because prokaryotes are everywhere, even when we can’t see them!