Turbidity method
In microbiology there are many times when there is need to either estimate or to determine the number of cells in a broth culture or liquid medium.
This estimation can be done by various direct and indirect methods. These include turbidity method, visual comparison of turbidity with known standard, standard plate count, direct microscopic count, measurement of cellular activity, cell mass determination. In our experiment to study the growth kinetics of E.coli we used turbidity method.
It is a quick and efficient method of estimating number of bacteria in liquid media. It is basically to measure the turbidity or cloudiness of culture and convert it into number of cells. Gradation in Turbidity
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This method is fast and majorly used when a large number of cultures are to be counted.
This method is achieved by determining the turbidity of different concentrations of microorganisms in liquid media. A standard curve can then be drawn, in which specific turbidity O.D reading is matched to species number of viable organisms.
Turbidity is measured by instrument
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1ml of this culture, i.e., 1% inoculum was added to 100ml liquid LB. The mixture is shaken and 4ml of this mix is taken in a cuvette and its optical density is measured at 600nm using a spectrophotometer, this is the 0 minute reading. The flask is incubated at 37°C in an incubator shaker. Then after 1hour another reading was taken for 4ml of the mixture. Subsequent readings were taken after 2,3,4..upto 18 hours. The O.D was reported in a tabulated form .Then a graph was plotted using these
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.
The setting in both Lord of the Flies and I Only Came to Use the Phone contributes to the dehumanization of the characters in each of the readings. The settings are both isolated, which is the cause of all the chaos that takes place because when you take a human being out of the comfort of society, they go back to their natural animalistic tendencies in order to survive. Survival of the fittest is present in these quotes. Also, the island archetype plays a huge role in both of the stories.
Through standard curve, we know the relationship between absorbance and cell concentration is that the more absorbance the higher cell concentration. The data was measured by spectrophotometer which can be used to measure the concentration of a known chemical substance. The higher value of dada means that the higher concentration. At the same time, it means that the higher rate of growth. The table and graph directly reflect the relationship between temperature and speed of growth of Euglenas. The graph has shown a trend that first rise after falling. The sharpest change belong room temperature and the gentle change is that when Bioreactors in fridge. Therefore, we can draw a conclusion that when in room temperature (about 23) there is the fastest speed of growth. Excessive temperature will affect the growth of euglenas.
In this report I will discuss different solutions for PVMS to help them improve network communications between the stores and head office, and centralize procedures for recording stock. This report will list the advantage and the disadvantage of each one.
During times of war, man is exposed to the most gruesome aspects of life such as death, starvation, and imprisonment. In some cases, the aftermath is even more disastrous, causing posttraumatic stress disorder, constant guilt, as well as physical and mental scarring, but these struggles are not the only things that humans can take away from the experience. War can bring out the appreciation of the little things in life, such as the safety people take for granted, the beauty of nature, and the kindness of others. These universal consequences of fighting all contribute to what war is really capable of doing, sometimes bringing out the best and worst in people, and constantly shaping society. In The Things They Carried, Tim O’Brien goes through this himself when he writes about setting up base camp in the Vietnamese pagoda, the return to site of Kiowa’s death, the story about the old poppa-san guide, and Mitchell Sanders’ “moment of peace”. When O’Brien includes these stories, it is not to insert joy into a tragedy, but rather to create a more wholesome and authentic feel into a tough, realistic war story. O’Brien’s’ “sweet” stories are there to show the hope he had during war, and also serve as a universal example that even in the darkest tunnels, it is always possible to find rays of light.
1. (45 pts) For each major (CS, IT, DET, IS), identify three important and uniquely identifying characteristics and describe how the four types of professionals would work together in a professional setting. Include information learned from the various instructors for each discipline. How do professionals from these areas work together?
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.
Research My first research experience took place from the Fall 2012 – Summer 2013 in a neurobiology laboratory (Dr. Daniel Plas) focused on Parkinson’s Disease. In this project an undergrad student and I were tasked with optimizing a cellular medium for neural growth of the model organism Lymnaea stagnalis. This was comprised of following established protocols and altering certain variables within the formulas (differing concentrations of ions, pH, et al.) to observe growth pattern differences in vitro.
The next day, 100 µL of an overnight culture of Salmonella growth will be transfer onto the center of a Petri plate containing tryptic soy agar where taken out from refrigerator. Sprea...
== § Test tubes X 11 § 0.10 molar dm -3 Copper (II) Sulphate solution § distilled water § egg albumen from 3 eggs. § Syringe X 12 § colorimeter § tripod § 100ml beaker § Bunsen burner § test tube holder § safety glasses § gloves § test tube pen § test tube method = == = =
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.
There were five test solutions used in this experiment, water being the control, which were mixed with a yeast solution to cause fermentation. A 1ml pipetman was used to measure 1 ml of each of the test solutions and placed them in separated test tubes. The 1 ml pipetman was then used to take 1ml of the yeast solution, and placed 1ml of yeast into the five test tubes all containing 1 ml of the test solutions. A 1ml graduated pipette was placed separately in each of the test tubes and extracted 1ml of the solutions into it. Once the mixture was in the pipette, someone from the group placed a piece of parafilm securely on the open end of the pipette and upon completion removed the top part of the graduated pipette.
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.
Research methodology should be understood as a whole, consisting of tools, methods of collecting, interpreting and analysing the data collected. These include: