Every organism requires a specific environment in order to survive. Bacteria alike, different types of bacteria are able to survive and reproduce in different types of environment. Some factors that affect the growth of bacteria include temperature, presence of certain gases and pH of the medium it is in.
In this experiment, the variable that was changed was temperature. Temperature is one significant factor that affects the growth of bacteria. Each bacterial culture has its own minimal, maximal and optimal temperatures. Bacteria thrive at their optimum temperature and are only able to survive between their minimum and maximum temperatures. If the temperature is significantly higher than the maximum temperature, the bacteria will be destroyed and this process is irreversible.
In addition, since bacterial growth is affected by many other factors such as pH of the medium and age of the bacteria, these factors must be kept constant throughout the experiment to ensure the accuracy of the results.
Different types of bacteria have different range of temperature they are able to survive. They are generally divided into three types: psychrophiles, mesophiles and thermophiles. Psychrophilic bacteria are able to survive in low temperatures ranging from about -10 to 20°C while thermophilic bacteria are able to thrive in high temperatures ranging from 40 to 75°C. These two types of bacteria are also known as extremophiles due to their ability to survive in extreme conditions. Mesophilic bacteria are bacteria that thrive in temperatures ranging from 10 to 45°C and usually have an optimum growth temperature of about 37°C (M. Furlong, n.d.).
Thermal death point (TDP) is the temperature at which a culture of organism is killed within a short...
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The duration of the experiment should be increased as the thermal death times of B. subtilis at 60, 70 and 80°C were unable to be determined within 110 minutes. The duration can be increased to 180 minutes so as to better investigate its thermal death times. If the presence of bacterial growth was still observed after 180 minutes of exposure, it can be assumed that B. subtilis is able to survive well in that temperature. An exposure time of one day can be carried out to confirm this assumption.
The abnormal presence of bacterial growth can be inspected under a microscope. If the organism inspected is not the bacteria used in the experiment, it means that the growth of the bacterial culture investigated is absent. By using this method, contamination by foreign substances in the surrounding air can be ruled out and the results would be more accurate.
I identified the genus and species of an unknown bacterial culture, #16, and I applied the following knowledge of morphologic, cultural and metabolic characteristics of the unknown microorganism according to the laboratory manual as well as my class notes and power point print outs. I was given an incubated agar slant labeled #16 and a rack of different tests to either examine or perform myself; the tests are as follows: Gram Stain; Nutrient Gelatin Test; Carbohydrate Fermentation; Dextrose, Lactose and Sucrose; IMVIC tests; Citrate, Indole, Mythel-Red and Vogues Proskauer test; as well as a Urease and TSI Test. Materials and Methods/Results Upon receiving the Microorganism (M.O.) #16, I prepared a slide by cleaning and drying it. Then, using a bottle of water I placed a sterile drop of water on the slide and used an inoculating loop, flame sterilized, I took a small sample of the unknown growth in my agar slant and smeared it onto the slide in a dime sized circle and then heat fixed it for ten minutes.
The first day an unknown sample was assigned to each group of students. The first test applied was a gram stain to test for gram positive or gram-negative bacteria. The morphology of the two types of bacteria was viewed under the microscope and recorded. Then the sample was put on agar plates using the quadrant streak method for isolation. There were three agar plates; one was incubated at room temperature, the second at 30 degrees Celsius, and the third at 37 degrees Celsius. By placing each plate at a different temperature optimal growth temperature can be predicted for both species of bacteria.
They can be found anywhere and identifying them becomes crucial to understanding their characteristics and their effects on other living things, especially humans. Biochemical testing helps us identify the microorganism present with great accuracy. The tests used in this experiment are rudimentary but are fundamental starting points for tests used in medical labs and helps students attain a better understanding of how tests are conducted in a real lab setting. The first step in this process is to use gram-staining technique to narrow down the unknown bacteria into one of the two big domains; gram-negative and gram-positive. Once the gram type is identified, biochemical tests are conducted to narrow down the specific bacterial species.
Input variables In this experiment there are two main factors that can affect the rate of the reaction. These key factors can change the rate of the reaction by either increasing it or decreasing it. These were considered and controlled so that they did not disrupt the success of the experiment. Temperature-
After the end of the experiment the unknown 10 sample was Staphylococcus epidermidis. Came to this conclusion by first beginning with a Gram Stain test. By doing this test it would be easier to determine which route to take on the man made flow chart. Gram positive and gram negative bacteria have a set of different tests to help determine the unknown bacterium. Based on the different tests that were conducted in lab during the semester it was determined that the blood agar, MSA, and catalase test are used for gram positive bacteria while Macconkey, EMB, TSI, and citrate tests are used for gram negative bacteria. The results of the gram stain test were cocci and purple. This indicated that the unknown bacteria were gram positive. The gram stain test eliminated Escherichia coli, Klebsiella pneumonia, Salmonella enterica, and Yersinia enterocolitica as choices because these bacteria are gram negative. Next a Blood Agar plate was used because in order to do a MSA or a Catalase test there needs to be a colony of the bacteria. The result of the Blood Agar plate was nonhemolytic. This indicated that there was no lysis of red blood cells. By looking at the plate there was no change in the medium. Next an MSA test was done and the results showed that there was growth but no color change. This illustrates that the unkown bacteria could tolerate high salt concentration but not ferment mannitol. The MSA plate eliminated Streptococcus pneumonia and Streptococcus pyogenes as choices since the bacteria can’t grow in high salt concentration. Staphylococcus aureus could be eliminated because not only did the unknown bacteria grow but also it didn’t change color to yellow. Lastly a Catalase test was done by taking a colony from the Blood Agar plate...
Bacillus anthracis is a non-motile elongated rod-shaped bacterium that will generate dormant spores with or without oxygen. When the spores are exposed to high levels of carbon dioxide and warmth they adjust into a ro...
During her presentation, Bonnie Bassler expends many different aspects of communication in a bacterial level and how successful communication is important to survival and efficient functioning. It is evident from her presentation that without a common language to communicate with, bacteria could not work as efficiently as they do, neither to immunize people nor create havoc in them. In her presentation, Bassler asserts the importance of the use of language in communication in bacteria, using rhetorical appeals – logical, ethical and emotional – and how it is consequently related to humans.
Temperature control is an important during desalting and storage. Once the salted fish is desalted, the microbial is rapidly growth in it (Oliveira et al., 2012).
The purpose of the lab was to show the effect of temperature on the rate of
Investigating the Effect of Temperature on the Fermentation of Yeast To fully investigate the effect of temperature on the rate of fermentation of yeast Background Information Yeast is a single-cell fungus, occurring in the soil and on plants, commonly used in the baking and alcohol industries. Every living thing requires energy to survive and through respiration, glucose is converted into energy. There are two types of respiration available to living cells are: 1.
Before conducting my experiment I will research into, amongst other things, the factors that affect the rate of a reaction. This is so that I may enough information to understand the effect of temperature on the rate of a reaction and also gain appropriate understanding to make a suitable prediction as to what the outcome of my experiment will be.
The first experiment conducted tested the effect different concentrations had on the bacteria Bacillus Subtilis. An agar plate was separated into four sections which contained: 100% Dettol, 50% Dettol, 25% Dettol and distilled water. It was hypothesised that the 100%, 50% and 25% Dettol would kill the most to least bacteria respectively and that the distilled water would not kill any bacteria. The hypothesis was mainly accurate however there was a small contradiction. The 100% Dettol killed the most bacteria with a kill zone covering 75% of its designated section and only 30 colonies remaining when examining the plates. The 50% Dettol was the second most successful at killing the Bacillus Subtilis. 50% of bacteria in the section were killed
Biological monitoring is basically evaluating a sterilization process by rendering highly resistant bacterial spores biologically inert. The highly resistant bacterial spores used varies depending on what kind of sterilizer was used. For example Bacillus stearothermophilus spores for steam and chemical vapor sterilizers, Bacillus subtilis spores for dry heat and ethylene oxide sterilizers. These specific Bacillus spores are used because they are more resistant, and present in greater numbers than are the common microbial contaminants found on patient care equipment. If it is proven that these spores have been killed, it is strongly implied that other potential pathogens in the load have also been killed.
Microbes are everywhere in the biosphere, and their presence invariably affects the environment in which they grow. The effects