Explain How You Can Grow Microorganisms In Liquid Media

In the beginning of lab, we were advised to obtain a nutrient agar petri plate, which is used for the cultivation of microbes supporting growth of non-fastidious organisms. Since it contains many nutrients, a wide variety of bacteria and fungi can grow. Taking the plate,

(Biology Dept.). 0.1 ml of E.coli K or 0.1ml of E.coli B was added to the 10 fold dilution. Using soft agar technique, the growth media mixture with E.coli was plated and incubated.

Background information: In this lab you will be looking at the growth of bacteria under different conditions to see the how populations of bacteria grow. Read about cells in the text or e-text. For everyone, in your e-text read chapter 13, sections 13.3 and 13.4 to learn more about bacteria. Then answer the questions below.

70µL of competent E.coli are added to both test tubes; pUC18 and Lux (Alberte et al., 2012). Both test tubes are then tapped and placed back into the ice bath for 15 minutes. While waiting, another test tube is obtained, filled with 35µL of competent cells and labeled NP for no plasmid. A water bath is preheated to 37 degrees Celsius and all three labeled test tubes are inserted into the bath for five minutes (Alberte et al., 2012). Using a sterile pipet 300µL of nutrient broth are inserted into both the control and Lux test tubes and 150µL are inserted to the no plasmid test tube to increase bacterial growth. All three test tubes are then incubated at 37 degrees for 45 minutes. Six agar plates are obtained and labeled to correspond each test tube, three of the plates contain ampicillin. A pipet is used to remove 130µl from each test tube containing a plasmid and insert it into the corresponding agar plate. For this, a cell spreader is first

Lab Day 1: After receiving my unknown bacteria, I streaked a TSA plate and incubated at 37°C for 48 hours. I then picked a single colony from the plate with my sterile loop and streaked a TSA slant and labeled it “Working Stock”. I did the same with another TSA slant and label the second one “Back-up Stock”. This would be the samples I used to complete the following procedures through the next four weeks to determine my unknown bacteria.

There were two tubes used in this process: the tube that contained the primary culture and the tube that contained the nutrient agar where the unknown bacteria would grow. First, the inoculating loop was flamed. After removing the caps of both the test tubes, they were flamed to prevent contamination of the unknown bacteria. The inoculating loop was cooled for a few seconds and was then placed into the test tube containing the bacteria. The inoculating loop with the bacteria was placed into the nutrient agar test tube for cultivation. Before the test tubes were capped, they were flamed once again. Also, isolation of the unknown bacteria had to completed. Nutrient agar was placed in the petri dish, and was left to gel for a few minutes. After the agar gelled, the inoculating loop was used to acquire bacteria and streak the unknown onto the plate for

Our world has changed dramatically since the day Antoine van Leeuwenhoek discovered microorganisms in 1676 using a simple microscope. In early days, scientists first thought life arose from inanimate materials. This theory, known as abiogenesis or spontaneous generation, was disproved later on by scientists including Lazarro Spallanzani and Louis Pasteur. The experiments conducted by these scientists showed that living things could only arise from preexisting life, or biogenesis. All life begins with a living cell, composing of five required components. These components are DNA, RNA, cell membrane, ribosome, and cytoplasm. As more investigations on bacteria were conducted, scientists were able to acquire a deeper knowledge of the microbiology and pathology of animals, plants, and humans.

Just like eukaryote species, not all bacteria species are identical in the way they behave, grow or interact with their environment (Mujtaba & DeJarnette, 2012). Microbes can be unique in the way they grow on nutrient agar (NA) plates. How their colonies form on the agar plates can also be an exclusive property of specific bacteria species. Microbes can grow in the presence of different nutrients, environments and can also be inhibited by or thrive in the presence of specific agents in the medium. For example inoculating a blood agar plate with the organism, can indicate its hemolysis activity, which it will fall in one of the three groups alpha (α), beta (β), or gamma (γ).

The unknown plate acted as the stock master plate, and was used to aseptically streak the unknown for isolation and was incubated at 37°C for 24 hours. After the incubation, a Gram stain was performed. Using an inoculating loop, a drop of DI water was placed on a clean slide, and a sample of bacteria was aseptically transferred and mixed in the DI water. The slide air dried for a couple of minutes, and was then heat fixed to keep the bacteria on the slide. Using a staining tray to hold the slide, 2 drops of crystal violet dye was placed on the dried bacteria and allowed to sit for 2 minutes (2). After the CV was set, DI water was used to rinse off any remaining dye. The smear was covered in Gram’s iodine for 1 minute. After a minute the iodine was rinsed off and the slide was tipped to the side to allow 2-3 drops of ethanol decolorizer to remove any remaining purple coloring. The slide was rinsed again, and the smear was covered with safranin for 30 seconds. After 30 seconds the slide was rinsed off and blotted dry with bibulous paper (2). The smear was then observed under a microscope to determine gram nature and

Purpose: The purpose of this experiment is to gain knowledge of the functions and operations of the compound light microscope and an immersion oil lens by observing prepared slides of various bacteria and blood slides. We are also learning to indentify and observe the various shapes and characteristics of bacteria, as well as, yogurt cultures (fresh and prepared) and blood samples under a microscopic view. We will also be able to distinguish between blood cultures and bacteria specimens.

Use the cotton swab to streak the five labeled nutrient agar plates with the E. Coli K12 bacteria from the tube.

The streak plate method is a rapid qualitative isolation method. The techniques commonly used for isolation of discrete colonies initially require that the number of organisms in the inoculums be reduced. It is essentially a dilution technique that involves spreading a loopful of

Purpose: To learn and employ aseptic technique and basic forms of culture media as well as become familiar with the basic requirements of microbial growth and the methods used to control microbial growth.

This experiment is about bacterial growth. We will demonstrate a bacterial growth curve using a closed system. Bacterial growth usually takes up to 12-24 hours to get an accurate result so we will be monitoring this growth between two classes. We also used different methods to determine bacterial growth as well as a few different calculations. One way of receiving data is by using a spectrophotometer where we will record the absorption at a given time to create the bacterial growth curve. We also used the plate count method after performing a serial dilution to calculate the actual cell density at different times given. By using this method we can count the population number of the same given and see the maximum cell density

Microorganisms can easily be found in water. In third world countries, this can pose a huge threat, because lots of people can get sick from drinking water. SODIS is a method used by many in undeveloped countries as means of attaining microbe-free water. It involves allowing water to stay exposed to sunlight in order to kill whatever microbes are living in it. For this experiment, microbial diversity was determined by collecting a sample of water of different from shaded water and water directly hit by the sunlight. Microbes were then cultured for 7 days. The abundance of the different colony types was then counted. Results exhibited that the community from the light area was more biodiverse. It was concluded that a possible reason for this is due to the different structures of bacteria, allowing some of them to sustain the light and others to be restricted by it. Since SODIS relies on light to kill microorganisms, it should be accompanied by another method that will also kill the bacteria that may survive in the water after being treated in the sunlight.