Serial dilution lab report

Typically, the dilution factor remains constant for each dilution, resulting in an exponential decrease in concentration. A tour of the microbiology lab section one duration. A serial dilutionis the dilution of a sample, in 10fold dilutions. A dilution is prepared by adding a specific amount of a concentrate to water to obtain a new volume and concentration. For example, in tenfold serial dilutions each successive dilution is one tenth of the previous dilution yielding dilution ratios of 110, 1100, 1, and so on. Introduction it is difficult to know and imagine the size of microorganisms, since they are too. For example, one in perhaps a million trypanosomes may undergo a. Estimation method for serial dilution experiments sciencedirect. Because of this, a variety of methods have been developed. This exercise is intended to familiarize us with using. The 10x dilution can then be diluted by a factor of 10 again by mixing it with 9 more parts of the diluent. Typically, the dilution factor remains constant for each dilution, resulting in an exponential decrease in. Use an appropriate dilution of the mixture with regard to the number of cells to be counted. These flasks range in size from 10 ml to 2000 ml are are carefully calibrated to a single volume.

Calculate the mass of sucrose needed to prepare 200 ml of 1. Serial dilution from econ 101 at institute of chemistry ceylon. Serial dilution is a series of dilutions used to determine the concentration or titer of a substance. The method maintains this accuracy even in the presence of dilution errors of up to 10% for both the aliquot and diluent volumes, microbial counts between 104 and 1012 colonyforming. You will use serial dilutions to create various concentrations of a popular solution iced tea or hot chocolate. Acids and bases usually come in concentrated form, as concentrates, but they are rarely used in this form. Divide the number of colonies counted by the dilution104, 105 or 106of the soil solution for each plate. Dilution is a decrease in a solutions concentration, whereas concentration is an increase in a solutions concentration. A dilution is the reduction of concentration of a solution by adding water. The following formula can easily be used to carry out a simple dilution. Hypothesis predict how the serial dilution of your drink solution will affect the colour, flavor, and other properties of the solution. Dilutions and concentrations introductory chemistry.

A dilution in chemistry is a process that reduces the concentration of a substance in a solution. Serial dilution lab in this unit we will be discussing measurements of concentration that us e both very big and very small numbers. The numbers of colony forming units cfus are divided by the product of the dilution factor and the volume of the plated diluted suspension to determine the number of bacteria per ml that were present in the original solution. A serial dilution is the stepwise dilution of a substance in solution.

Lab reports can also be written for college classes, as well as other professional areas including engineering and computer sciences. Sample lab 1 report 2 lab report 1 sample serial dilution of a bacterial culture introduction genetic analysis often requires the measurement of the frequency of events that are not likely. Spectrophotometry page 7 of 10 single dilutions background stock solutions are constantly diluted in biological lab settings. As shown in the illustration below, it begins when 1 ml of the bacterial sample is added to 9 ml, and it is mixed together creating. The numbers of colony forming units cfus are divided by the product of the dilution factor and the volume of the plated diluted suspension to determine the number of bacteria per ml that. A tenfold dilution for each step is called a logarithmic dilution or log dilution and a 3. Lab report 1 isolation, identification and use of serial dilutions to estimate cell numbers. For example, a tenfold serial dilution could result in the following concentrations. Pdf estimation method for serial dilution experiments. Pdf lab report of microbiology akbar haqi academia. Bacteria present in a sample by serial dilution agar plating. Sample lab 1 report 2 lab report 1 sample serial dilution of a bacterial culture introduction genetic analysis often requires the measurement of the frequency of events that are not likely to occur except in a large sample. So you can calculate the total effective dilution as 107 106 x 101 107.

Complete lab report for experiment 1 of the applied microbiology lab work. A microbe is an organism that is microscopic and submicroscopic, which is. Then, 1 ml from that mixture is added to 9 ml, and it is mixed together a 102 dilution. A solution is the mixture of 2 or more substances in the same phase.

Note that serial dilution is a special case of series of dilutions. Dilutions in the range 101 110 to 108 1100,000,000 are generally used, although with particular types of samples the range of dilutions can be restricted. Repeat this dilution step three times, each time with 1 ml of the previous suspension and a 9ml deionized water blank. Prepare the dilution series stock solution of food coloring as outlined in figure 5. Preparing and diluting solutions loudoun county public. This webinar is intended to give a brief introduction into the mathematics of making solutions commonly used in a research setting. Culturing and enumerating bacteria from soil samples.

Also note that you end up with 5 ml of solution in each tube. However, the numbers of microorganisms in a given sample are required to know in certain aspect such as dairy industries, diseases investigation, and so on. Bacteria present in a sample by serial dilution agar. The extent of bacterial activity in a given sample in a definite set of conditions mainly depends on the total number of bacteria present in it irrespective of their species. In order to calculate the concentration of dilution, the following formula may be used. A serial dilution is a series of sequential dilutions used to reduce a dense culture of cells to a more usable concentration. Sample lab report introduction to the spectrophotometer.

Each dilution will reduce the concentration of bacteria by a specific. The format of the report is that of a journal submission. Lab math solutions, dilutions, concentrations and molarity. The organization, accuracy, completeness, interest in topic, results and explanations determine report grade. A series of five dilutions is made of this first dilution by diluting it. The whys and hows of writing a lab report this author provides an excellent student lab report format, explains how it adapts to different science disciplines, and suggests simple labs to familiarize students with it. A serial dilution is any dilution in which the concentration decreases by the same factor in each successive step in serial dilutions, you multiply the dilution factors for each. Serial dilution method protocol step wise explanation duration. Obviously, the bod test is not the most scientifically based test we perform. In this video i discuss how we made a serial dilution during the lab, as well as why we made that serial dilution in the first place. From the 102 dilution, 1 ml is dropped into a sterilised petri. Mar 29, 2019 a serial dilution is the repeated dilution of a solution to amplify the dilution factor quickly. As shown in the illustration below, it begins when 1 ml of the bacterial sample is added to 9 ml, and it is mixed together creating a 101 dilution.

Introduction it is difficult to know and imagine the size of microorganisms, since they are too small to. You then plated 100 l not a full ml of that dilution, which is in effect an additional 101 dilution 100ll. Prelab questions show work and include in your lab report 1. To enumerate bacteria present in a sample by serial dilution agar plating method or total plate count tpc method. Serial dilutions reduce the concentration of a sample in small steps or fractions. Quantitative estimation of the number of viable microorganisms in bacteriological samples has been a mainstay of the microbiological laboratory for more than onehundred. Introduction microorganism is an organism that is microscopic or submicroscopic, which is too small to be seen under naked eyes. Find the number of cultivatable bacteria in the original gram of soil by averaging the results from each countable plate. With no tube in the machine, the zero control was turned to adjust the needle to a 0% transmittanceinfinite optical density od. Serial dilution besides the more conventional uses described above, serial dilution may also be used to reduce the concentration of microscopic organisms or cells in a sample. A serial dilution is a series of simple dilutions which amplifies the dilution factor quickly. Key is licensed under a creative commons attributionnoncommercialsharealike 4. In order to obtain a certain concentration of acid or base, dilutions are made. A series of five dilutions is made of this first dilution by diluting it 110, rediluting 110, and then three times more, each resulting solution then being a 110 dilution of the previous one in the series.

Assume that the ice teahot chocolate mix is essentially sucrose sugar, c12h22o11. It is critical that you master both serial and simple single. Serial dilution method colony forming unit microorganism. Dilutions and concentrations introductory chemistry 1st. Nov 04, 2011 in this video i discuss how we made a serial dilution during the lab, as well as why we made that serial dilution in the first place. A microbe is an organism that is microscopic and submicroscopic, which is too tiny to be viewed under a naked eye.

Upon completion of this lab, the student should be able to proficiently calculate molarities for solutions. This results in serial dilutions of 101 through 105 grams of soil per ml. Lab report overview each student is responsible for 50% of lab work, and for individual, original reports. Find the number of cultivatable bacteria in the original gram of soil by. For this lab, we will assume the g ram f ormula ma ss of koolaid is 40. While you may already make solutions in the lab by following recipes, we hope this webinar will help you understand the concepts involved so that you can. This exercise is intended to familiarize us with using scientific notation to express big and small number easily and the process of using serial dilutions to make concentrations of known values. This author provides an excellent student labreport format, explains how it adapts to different science disciplines, and suggests simple labs to familiarize students with it. Booker microbiology 2310 lab report 3 serial dilutions october 15, 2017 introduction. Refer to lab report requirements on the class website. Using a turntable and sterile bent glass rod see fig. X research source its commonly performed in experiments requiring highly diluted solutions, such as those involving concentration curves on a logarithmic scale or when you are determining the density of bacteria.

As shown in the illustration below, it begins when 1 ml of the bacterial sample is added to 9 ml, and it is mixed together creating a 101. The easiest method is to make a series of 1 in 10 dilutions. Be careful to not crash the objective into the hemocytometer at the time of focusing. If the sample is not dissolved well, the cells become crowded and will be difficult to count. You had physically diluted the culture by 106 at this point in your dilution scheme. These include quantifying the number of bacteria in a sample using plate counts and the development of standard curves for quantitative colorimetric, radiometric, and enzymatic assays. A serial dilution is the dilution of a sample, in 10fold dilutions.

Serial dilutions may be used to prepare a series of standard concentrations for a biochemical assay, or to dilute a very dense culture of microorganisms to a concentration suitable. We will report concentration in cfu per milliliter. Here is an example of a lab report that was actually submitted and received a perfect grade along with stepbystep instructions on writing an effective lab report. Serial dilution many procedures performed in modern biology and chemistry laboratories require sets of solutions that cover a range of concentration s.

It is critical that you master both serial and simple single dilutions. Lab report 1 isolation, identification and use of serial. Serial dilution lab report the instructions below are designed to keep you safe in the laboratory. Jan 27, 2020 to prepare a standard solution a piece of lab equipment called a volumetric flask should be used. Prelab questions show work and include in your lab report. Often, a worker will need to change the concentration of a solution by.