Bacterial Colonies in Your Environment

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Biology Lab Report Bacterial Colonies in Your Environment Purpose The purpose of this lab is to culture, examine and describe microorganisms (bacterial colonies) from sources in daily surroundings that we are exposed to. Variables and Controls The independent variable was the places we decided to swab for bacteria. The dependent variable was the types of bacteria that grew within the agar plate The controlled variables were the temperature in the sir, how tight the agar plate was sealed and how much food was in the agar plate. Materials -a sterilized agar plate (with lid) -markers -soap and water -clear tape -sterile cotton swabs Lab Safety In this lab we needed to wash our hands constantly before and after the lab. We were dealing with bacteria that has the ability to be harmful and to avoid illness/sickness we need to thoroughly wash our hands and be careful around the bacteria. Another precaution to take was to not cough into or put any bacteria from our bodies into the agar plate. Those bacteria could be extremely dangerous and shouldn’t be cultivated. Observations Located on final page(s) Application Questions 1. The purpose of heating the agar plates in the autoclave prior to inoculating them with microorganisms was to make sure that the lab results were exact. The plates might have not been properly cleaned beforehand or the bacteria in the air/where they were stored might still lay on the plate. Due to those bacteria the lab results might have turned out differently because we cultured different bacteria from places we did NOT swab. To prevent this we must sterile the plates. Bacteria dies at high temperatures so the plates were heated to kill off any lingering bacteria that may have been present on the agar plate. 2. A sterile cotton swab was used as opposed to a regular one because contamination might have
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