a) What is the dilution factor if you add a 1ml aliquot of a specimen to 99ml of diluent? b)How to make 500ml of a 1:250 dilution?

Q: What are the expected problems in the centrifuge in case of imbalance of samples ? *

A: Centrifugation is a process of separation of molecules from mixtures by applying centrifugal force…

Q: to dilute a sample by 1/3. For a final volume of 27 ml, how much sample would you add to how much…

A: The concentration of the solution fluctuates as it is diluted, but the number of moles of reactant…

Q: Why is dilution a necessary part of pure culture preparation?

A: The pure culture consists of a single microorganism. This culture helps to easily evaluate the…

Q: Give two reasons for heating the slide after the smear is air dried?

A: Smear is the thin film of the sample that is spread over the slide to be observed in the microscope.…

Q: What will you do if you see bubbles forming on the gel after pouring it onto the gel caster/tray?

A: In laboratory, Electrophoresis is a technique for separation of the proteins and nucleic acid. The…

Q: How would you determine the contents of the test tubes if all of the samples were transparent?

A: The study of chemical reactions that occurs within living organisms is called biochemistry. This…

Q: How would you perform a 100-fold dilution, if you want the final volume to be 15mL? What volume of…

A: Dilution is the process of decreasing the concentration of a solute in a solution. To dilute a…

Q: Why is there a need to use a staining agent in observing the specimen?

A: Staining agent:          The things that owes-out stains were recognized as staining agent,…

Q: Why would the optical tweezers be a method superior to dilution and liquid enrichment for obtaining…

A: Optical tweezers have been used to trap dielectric spheres, viruses, bacteria, living cells,…

Q: yield

A: The Dische's test is a chemical test that is utilized to detect the presence of DNA in a solution.It…

Q: What is the purpose for testing a specimen for hydrogen sulfide production?

A: Hydrogen sulfide is produced when a bacterial strain reduces the sulfur compounds.  The specimens…

Q: How can polarography detect the analyte?

A: Jaroslav Heyrovsky discovered polarographic method   Polarography is a simple method in analytical…

Q: What are high level disinfectants? What is an example of one? What is the method of action and the…

A: Disinfectants are chemicals that are used to kill the microorganisms present in the surroundings.…

Q: | || | | || | || 1 45 Using the figure, which lane has a poor quality sample and is possibly…

A: Electrophoresis (Gel electrophoresis) is commonly used in labs to study a mixture of biomolecules…

Q: You are testing unpasteurized milk for the presence of bacterial contamination. Starting from the…

A:

Q: If the 10-9 plate was counted to have 155 colonies on it, would the CFU/mL be 1.55*1011? If not,…

A: CFU  Colony forming unit it a method to calculate the number of microorganisms in a culture media.

Q: Why is it necessary to use immersion oil when the 100X objective is used'

A: Note - we answer one question at a time. Immersion oil is transparent and has specific viscosity and…

Q: If you observe a specimen under this 20X objective and the specimen spans one-quarter of the field…

A: A light microscope is common equipment in most laboratories. It comes with one or two eyepieces…

Q: Why is there a need to use acids and boil the sample in maceration?

A: Maceration is a common method of obtaining medicinal plants, it is an extraction process in which…

Q: What happened when potato strip placed in salt water?

A: 1) A solution mixture that exhibits a higher concentration of salt than the surrounding medium. Then…

Q: What is the purpose of the sodium thiosulphate in the testing of treated water?

A: Testing of wastewater and treated water both demand a standardized process to be followed to obtain…

Q: If there is 50 bacterial colonies on a 1:1000 dilution streak plate. How many cfu/mL are there?

A: Introduction: A CFU stands for colony-forming units. It is a unit that we use for estimating the…

Q: Why is the incubation temperature criticalwhen using the Filter Method when testing water samples?

A: Incubation temperature is critical for bacterial growth if this temperature is too high or too low…

Q: What is the importance of the Nitrate test? What information can we gather from this test? Please…

A: Nitrate broth used in the nitrate test contains nutrients and potassium nitrate as a source of…

Q: What is the purpose of adding sodium bicarbonate to a culture medium?

A: >> The purpose of adding sodium bicarbonate to animal culture medium is that it acts as a…

Q: Why is it necessary to perform a plate count in conjunction with the turbidimetry procedure?

A: Plate counting is one of the most fundamental techniques used in microbiology. It is used to…

Q: With the constants you have for each objective, compute for the sizes of the given cells below.…

A: As we know that cell is the structural and functional unit of life it performing all the essential…

Q: What is the estimated size of the specimen under a 10x10 ocular micrometer under HPO? (Take note:…

A: The specimen size can be calculated by using the number of ocular units occupied by it. Here simply…

Q: why In spread-plate technique, the bacterial suspension volume  should not exceed 0.1ml.

A: Spread plate method is a technique which uses a Petri plate or dish in which a growth medium or gar…

Q: What special precautions must be taken when using the oil immersion (100x) objective?

A: Using oil immersion reduces the air gap between the glass slide and the objective lens. This air gap…

Q: How many bacteria would be in 1ml of the sample if you counted 134 colonies on the 1:1,000 dilution?

A:

Q: Why do we add powdered zinc to the nitrate reduction test?

A: Bacteria are prokaryotic simple unicellular organisms. Their mode of respiration may be aerobic or…

Q: To measure the culture temperature, why is the thermometer placed in a tube separate from the…

A: A microbe or microorganism is a microscopic organism that is too small to be seen with the naked…

Q: What is the best streaking technique in a culture media? Explain

A: In microbiology, there are five I's that symbolise five different procedures used in the laboratory…

Q: Write the instructions, reagents, principles and the procedures for the following.  1. Periodic acid…

A: (AS PER OUR GUIDELINES WE ARE PROVIDING YOU ANSWER OF 1ST TWO QUESTIONS. YOU CAN POST OTHER…

Q: Why should the specimen be albumin free when performing the chloride test for urine?

A: Urine specimen should be free from albumin when performing the chloride test due to the following…

Q: What steps are required to verify both contact with the sterilant and sterilization of an instrument…

A: Sterilization is the process that eliminates, removes, kills or deactivates the microorganism such…

Q: Why is it necessary to cut thin sections of the tissue sample from a specimen using a microtome?

A: Microtomes are specialized cutting instruments that produce very thin slices of tissues so that the…

Q: Why sometimes specimen may show organisms under the microscope but not appear in the culture media?

A: Introduction  We are surrounded by various pathogens such as bacteria, viruses, fungus etc. Bacteria…

Q: What is the difference between a tincture and an aqueous solution?

A: Given: Explain the difference between a tincture and an aqueous solution

Q: Why did we add agar after we measure the pH?

A: pH means p stands for potential or power.H stands for Hydrogen atom.It is the power of the Hydrogen…

Q: why is it necessary to use oil immersion on oil objective ?

A: The oil immersion is the technique of light microscopy, which is used to increase the resolving…

Q: Describe how you would make 10 ml of a 1:500 dilution of bacteria by performing TWO SEPARATE…

A: A serial dilution is the stepwise dilution of a substance in solution. Normally the dilution factor…

Q: After a urine culture, 95 colonies are counted on a plate inoculated with 1 uL of urine samplpe.…

A: The CFU count gives us the viable number of cells present in the sample.

Q: You carry out a dilution adding 20 mL of solution A and 80 mL of water. This dilution can NOT be…

A: In laboratory, various concentration of substances are needed for different experiments. In some…

Q: What are the immersion media that need to be used?

A: Immersion media is used to increase the numerical aperture of the microscope by a factor equal to…

Q: What is the purpose of setting the spectrophotometer to zero absorbance using a blank solution?

A: Spectroscopy is a procedure utilized for the evaluation, portrayal, and basic investigation of a…

Q: In RPR test, Why is it necessary to rotate the slide/card?

A: RPR stands for Rapid Plasma Reagin. It is done to detect syphilis.

Q: What is the purpose of examining your specimen slide using low power objective first nefore high…

A: Objective lens are magnifying lens that functions to magnify an image. These lens make an important…