Five Sterile Petri Disheses
Abstract
Mutations play an important role in evolution that introduces new branches to the diversity of life. This experiment was conducted to understand the relationship between the length of exposure to the UV to the rate of mutations and the growth of bacterial cultures. Five plates containing microscopic organisms were arranged and exposed to various lengths of UV light. The test was a quantitative test to effectively the rate at which changes happen at the distinctive length of UV introduction. As the exposure time of UV light increased, the red-pigmented bacteria colonies turned white due to mutation.Therefore, both growth and mutation in the bacteria are negatively affected by increasing exposure of UV light. Consequently, both development and …show more content…
Five sterile petri-dishes were each labeled with the time that the plate would be exposed to UV radiation (0 seconds or negative control, 15 seconds, 30 seconds, 45 seconds, and 60 seconds). Aseptic technique was critical during each transfer of agars. Plain 50 agar was poured equally to each plate labeled. A cotton end of the applicator stick was wet with the liquid culture of bacteria, Serratia marcescens, and applied on the surface of agar the same way it was carried out to cover the agar gradient in the first part of the experiment. Plates were prepared for the UV exposure. It was in this step that each plate was separated into five different treatment groups. Each plate was exposed one at a time to the radiation according to the time labeled on the cover. Immediately after removing plates from the UV box were wrapped the plates in foil to prevent any light from entering the plates. Photo-activation of DNA repair mechanism could usually reduce the damage by the UV radiation and might introduce an undesirable variable to the
Mutations play an important role in evolution that introduces new branches to the diversity of life. This experiment was conducted to understand the relationship between the length of exposure to the UV to the rate of mutations and the growth of bacterial cultures. Five plates containing microscopic organisms were arranged and exposed to various lengths of UV light. The test was a quantitative test to effectively the rate at which changes happen at the distinctive length of UV introduction. As the exposure time of UV light increased, the red-pigmented bacteria colonies turned white due to mutation.Therefore, both growth and mutation in the bacteria are negatively affected by increasing exposure of UV light. Consequently, both development and …show more content…
Five sterile petri-dishes were each labeled with the time that the plate would be exposed to UV radiation (0 seconds or negative control, 15 seconds, 30 seconds, 45 seconds, and 60 seconds). Aseptic technique was critical during each transfer of agars. Plain 50 agar was poured equally to each plate labeled. A cotton end of the applicator stick was wet with the liquid culture of bacteria, Serratia marcescens, and applied on the surface of agar the same way it was carried out to cover the agar gradient in the first part of the experiment. Plates were prepared for the UV exposure. It was in this step that each plate was separated into five different treatment groups. Each plate was exposed one at a time to the radiation according to the time labeled on the cover. Immediately after removing plates from the UV box were wrapped the plates in foil to prevent any light from entering the plates. Photo-activation of DNA repair mechanism could usually reduce the damage by the UV radiation and might introduce an undesirable variable to the