Transcript Slide 1
The Relationship of Ultraviolet Light to the Growth of Micrococcus luteus and Serratia marcescens Catherine Francis 2009 Research Education for Teachers Northeastern University, Boston, MA Essential questions 1. What are the characteristics of a prokaryotic organism? 2. Does ultraviolet light influence the growth and health of living organisms? 3. What sterile techniques are unique to microbiology? Hypothesis If we expose pigmented bacteria to ultraviolet light, then the growth will be reduced. Purpose High school biology students will determine if ultraviolet radiation influences the growth of pigmented bacteria. Upon successful completion of this lesson students will be able to grow bacteria on a petri dish using the quadrant streak method. The control group of bacteria will be grown without ultraviolet light while the experimental group will be grown with ultraviolet light from a germicidal UV lamp. After the bacteria is grown overnight in an incubator, the number of colonies will be counted in order to determine the influence of ultraviolet light. Materials • • • • • • • • • Safety Goggles Disposable Nitrile Gloves Micrococcus luteus (yellow) Serratia marcescens (red) Sterile prepoured plates of nutrient agar Sterile Toothpicks Germicidal Lamp Incubator Bleach www.marine csiro.au/ Serratia marcescens www.student.ccbc.md.edu Serratia marcescens www.inst.bact.wisc.edu/inst/index Micrococcus luteus Micrococcus luteus www.homepages.wmich.edu References "Encyclopedia - Britannica Online Encyclopedia." Encyclopedia Britannica Online Encyclopedia. 21 July 2009 <http://www.britannica.com> . Gray, John. "PG.com." PG.com. 21 July 2009 <http://pg.com>. "Home - The Skin Cancer Foundation." Home - The Skin Cancer Foundation. 21 July 2009 <http://skincancer.org>. Lerner, Lee, and Brenda Wilmoth. "Ultraviolet Rays and Radiation." World of Earth Science 2 (2003): 605. Gale Virtual Reference Library. 21 July 2009. Wade, Jeffrey, and Richard Coffin. Molecular Studies of Ultraviolet Radiation Effects on Marine Bacteria. Pensacola: Center for Environmental Diagnostics and Bioremediation, University of West Florida, 2009. Zeman, Gary. "Health Physics Society." Health Physics Society. 21 July 2009 <http://hps.org>. Zenoff, V, and M Farias. "Diverse Responses to UV-B Radiation and Repair Mechanisms of Bacteria Isolated from High Altitude Aquatic Environments." Applied and Environmental Microbiology 2.12 (2006): 7857-7863.