The purpose of this experiment is to see how much bacteria can and will grow in common places in a typical high school. Common places can mean many things, including anything from water fountain spouts to computer keyboards. Such objects can hold up to 2,700,000 colony forming units per square inch (or CFU/in sq)(NSF). A colony forming unit is the unit used to find an estimate of the number of cells of a bacteria. This unit of measurement is commonly utilized in the subject of microbiology. Most commonly, a bacterium will reproduce asexually through the process of binary fission (Koch, 2002). Binary fission is the process of a bacterium growing to a certain size and then splitting in two identical daughter organisms, both carrying …show more content…
The first phase is known as the lag phase. In this phase, the bacteria learns to adapt to the unfamiliar nutrient-filled environment it is placed. The second phase is called the log phase. During the log phase, the bacteria experiences exponential growth. Nutrients are metabolised at maximum speed until all of the nutrients are entirely consumed. At this point, the bacteria starts to limit growth. The third phase is the stationary phase and is a result of depleted nutrients. This is the phase where the bacteria ceases its metabolic activities. The final phase is simply the death phase, where the bacteria die due to the lack of nourishment …show more content…
An agar plate is a Petri dish that contains a combination of agar and nutrients that help microorganisms grow. The proper method of setting microorganisms on an agar plate is know as “streaking”. In order to streak, the microorganisms are placed on a sterile swab or metal wire, which is then dragged lightly against the agar solution, leaving behind the microorganisms. The amount of organisms is greatest at the beginning of the streak and lowest at the end of the streak (Madigan, 2006). But what is agar? Agar is a substance similar in consistency to jelly that is created using algae (ODE, 2005). It is difficult to consume for most organisms which is why it is ideal for microbial growth as the organisms will consume the nutrients mixed into the agar but not the agar itself. Agar is commonly sold powdered and must be mixed with water to form the gelatinous shape it is known for. Of course, additional ingredients are added to suit the microorganism’s nutritional