While thinking about Experiment 3, Aseptic Technique and Microbe Culture, I realized the large amount of microorganisms that can be found in everyday life. Many different types are found in the human body. These experiments focused on two types of bacteria. The first was Staphylococcus epidermidis, found on the skin, and the second was Lactobacillus acidophilus, found in the gastrointestinal tract. Both have similar growing requirements in terms of temperature, however, different growing environments are used. For growth to occur, microorganisms need to obtain energy. One of these methods is to either use oxygen or not use oxygen. Microorganisms that require oxygen are obligate aerobes. It is essential for them to obtain oxygen for their growth, there they receive energy from aerobic respiration which requires oxygen. Microorganisms that do not necessarily require oxygen are called facultative anaerobes. These organisms are capable of growing with or without the presence of oxygen. They obtain energy there through aerobic respiration if oxygen is present. Facultative anaerobic bacteria are capable of switching to fermentation or anaerobic respiration if no oxygen is present. Staphylococcus epidermidis and Lactobacillus acidophilus are both facultative anaerobic bacteria that do not always require oxygen to grow. There are also temperature requirements for their growth to occur. Microorganisms are divided into several groups based on preferred temperatures. The first type is psyrophiles. These bacteria prefer the cold. Usually found in a negative temperature of five degrees Celsius to fifteen degrees Celsius. Typically located in the Antarctic and Arctic regions, they feed on runoff from glaciers. The next one is mesophiles. These bacteria prefer the middle of the paper...the surface for their growth. And finally, stab or deep tubes are tubes filled with hardened agar medium and are used by pressing the inoculum into the agar. The two different media used in this experiment were nutrient broth for the growth of Staphylococcus epidermidis and MRS broth used for the culture of Lactobacillus acidophilus. After observing both cultures after twenty-four hours, neither showed any signs of growth. It was only after forty-eight hours that there were signs of growth. Nutrient broth containing Staphylococcus epidermidis has become cloudy or turbid. MRS broth containing Lactobacillus acidophilus showed increased sediment. I feel like I haven't seen any growth after twenty-four hours due to possible improper temperature. I adjusted the temperature to try to stay at thirty-seven degrees Celsius..