Prediction: If UV light mutates the DNA of Serratia Marcescens then the red pigment colonies of the bacteria will no longer be produced.
Independent Variable: Ultra Violet Radiation
Dependent Variable: The color change of the bacteria Serratia Marcescens from red to white and the survival of the bacteria.
Control: Nutrient agar plate with streaks of Serratia Marcescens without exposure to UV light.
Results:
Figure 1: Represents the nutrient agar plate used as the control that was not exposed to the UV light. Each quadrant represents a 10 sec exposure to the bacteria increasing to 40 secs.
Serratia Marcescens bacteria streaked
Figure 2: Represents the nutrient agar plate used as the second control with the bacteria that was exposed to the UV light but with the lid on the plate. Each quadrant represents a 10 sec exposure to the bacteria increasing to 40 secs.
Figure 3: Represents the Experiment plate of nutrient agar with the bacteria that was exposed to UV light without the lid on the plate. Each quadrant represents a 10 sec exposure to the bacteria increasing to 40 secs.
Serratia Marcescens is a gram negative rod shaped bacteria, containing the red pigment called prodigiosin. After the initial streaking of the 3 plates with Serratia Marcescens there were no visible differences. Two of the three plates were exposed to UV light, the experimental plate was exposed to UV without the plate on it whereas the second control plate was exposed to the UV light with the plate lid. The first control plate was streaked with the bacteria but was not
Bibliography: 1.Lab Manual 2. Zion, Michal, et al. "UV Radiation Damage And Bacterial DNA Repair Systems." Journal Of Biological Education (Society of Biology) 41.1 (2006): 30-33. Academic Search Complete. Web 15 Oct. 2014.