) If you counted 500 CFU’s in the petri dish for number 6 and 5000 CFU’s in petri dish for number 7, what would be the most justifiable explanation for this? 19) If the original sample’s concentration was 12 bacterial cells, what do you expect the count to be?

Q: You have a suspension of cells at a concentration of 5 x 106 cells/mL in culture media. The protocol…

A: Serial dilution process is routinely used to calculate the concentration of unknown solution. The…

Q: You have performed a serial dilution of an unknown sample and counted 73 CFU on a countable plate…

A: Serial dilution is method of diluting a bacterial culture in succession. The process reduces the…

Q: If there is a sample having 3.5x10^5 CFU/ml, and this cell count came from a sample of the original…

A: CFU stands for colony-forming unit that gives rise to a particular colony. It is generally assumed…

Q: 1. A plate with a final dilution factor of 107 produced 210 colonies. a) What was the original…

A: Dilution is the process of diluting or mixing two or more substances or compounds; it is also known…

Q: Two different bacterial samples, A and B, were inoculated onto SIM media. What can you conclude…

A: SIM (Sulfide, Indole and Motility) test is done to differentiate the Gram negative bacilli based on…

Q: How to count the number of colonies forming units per milliliter (CFUs per ml) of the sample?

A: A viable cell is one that has the ability to divide and form a colony. The colony-forming unit (CFU)…

Q: Three grams of soil from the ground were added to 27 mL of sterile water and shaken vigorously.…

A: The initial dilution was a 1/100 dilution, followed by 4 1/10 dilutions. So, the calculate the CFU…

Q: Per the USDA, whole, unpasteurized fresh eggs can contain no more than 50,000 CFU/mL bacteria in a…

A: The serial dilution is a process that is routinely used in microbiology laboratories for the…

Q: How many colonies would you expect to count at each 5-fold dilution (5-1 until 5-6), when you have…

A: Serial dilution is the technique for step by step dilution of any sample in definite dilution…

Q: Why should the cell density of the inoculum be as small as possible? Why can we not standardize the…

A: The process of introduction of microbes into a nutrient media or other similar environments which…

Q: You take 10 ml of a stock solution, which is at a concentration of 1000 phage/ml, and dilute it to a…

A: A serial dilution is a laboratory technique that uses a series of consecutive dilution steps to…

Q: Describe how you would prepare a dilution series of a 1 x 107 CFU/mL culture to the 10-8 dilution…

A: Serial dilutions is a process of making step by step dilutions of a substance. It is formed by…

Q: You have spread 0.1ml of a 1x10-8 diluted bacterial culture sample on a Petridish and counted 35…

A: Given  Volume plated = 0.1ml  Total dilution = 108  Number of colony = 35

Q: 4 mL of 10% TCA solution was added to 1 mL of serum and after mixing, it was waited for two minutes…

A: Calibration graphs are used to estimate the concentration of unknown sample by plotting it against…

Q: If 0.1 ml of a 1 * 10−6 dilution plate contains 56 colonies, calculate thenumber of cells per ml of…

A: In the given example, 0.1 ml of a 1 * 10−6 dilution plate contains 56 colonies. The number of cells…

Q: A microbiology student was given a mixed culture of two different gram positive bacteria species to…

A: In Microbiology, we grow bacteria on culture medium. Culture media contains specific mixture of…

Q: Using a dilution series is a way to transfer the very small volumes of original culture necessary to…

A: Answer -To determine the volume of the original bacterial culture required to obtain a specific…

Q: CFU

A: CFU:It stands stands for Colony-Forming Unit. It is a measure used to estimate the number of viable…

Q: You prepared a 7x 10^5x dilution from your bacterial culture, plated 0.2 ml of it on a Petridish and…

A: A colony-forming unit (cfu) is a unit used in microbiology to estimate the number of viable bacteria…

Q: With a plate count average of 297 and a final dilution on the plate of 1:1,000 ; what is the viable…

A: Bacteria are the prokaryotic, unicellular organisms that are sometimes pathogenic in nature. The…

Q: You inoculated a culture with an initial cell count of 6.5x10^3 cells. The generation time for this…

A: Bacteria are prokaryotic organism and divides by binary fission that is responsible for doubling the…

Q: The following data were obtained by incubating gram-positive bacteria in nutrient medium +…

A: Gram-positive bacteria are bacteria that test positive in the Gram stain test, which has…

Q: What is the amount (mL) of pre-culture (108 cell/mL) necessary to inoculate (to add) in a 2-liter…

A: Culture media is a solid or semisolid substance used to support the growth of microorganisms. It is…

Q: if 250 colonies are present on a pour plate made from10^5 dilution, how many colonies should grow on…

A: Serial dilution method is the process of diluting our culture in a sequential manner. This is done…

Q: A serial dilution of overnight E.coli culture was performed by pipetting 1ml of a bacterial culture…

A: A growth medium is intended to promote the growth of a variety of microorganisms or cells by the…

Q: If the purity of DNA sample is below 1.8 A260/A280, where did the protein contamination come from?

A: The absorbance ratio at 260 nm & 280 nm is used to determine the quality of DNA & RNA.  A…

Q: ) = 80e−0.05t + 8(t + 1)−0.5. Her model says that C(t) is the number of coliform group bacteria…

A: If considering the equation C(t) = 80e−0.05t + 8(t + 1)−0.5  Time is zero initially then  C =…

Q: Tidal Volume

A: Different animals have different lung capacities based on their activities. Air in the lungs is…

Q: thanol has been carried over into your DNA sample (two answers possible here, select both of them)…

A: DNA is not soluble in ethanol . But when ethanol is there DNA gets separated by forming white…

Q: Why do we use the term CFU (colony forming unit) instead of reporting bacteria per ml? Explain.

A: The  bacterial species are responsible for causing several diseases within the human body. So, for…

Q: What is the amount (mL) of pre-culture (108 cell/mL) necessary to inoculate (to add) in a 2-liter…

A: Culture media is a solid or semisolid substance used to support the growth of microorganisms. It is…

Q: You perform several tests on an unidentified bacterial species and get the results below. Based on…

A: Bacterial identification is the process of determining the specific type, species, or strain of…

Q: A bacterial culture is initially composed of 100 cells. After 1 hour the number of bacteria is 1.5…

A: The given answer calculates how long it will take for bacterial populations to quadruple in perfect…

Q: You plated 1.0 mL of a sample diluted by a factor of 10^-5 and you counted 50 comonies after…

A: The stock concentration of the bacteria can be determined by counting the colonies formed on the…

Q: You perform the Methyl-Red(MR)& Voges-Proskauer(VP)test and gather the followingresults:…

A: Since you have asked multiple questions, we will solve the first question for you. If you want any…

Q: You use a spectrophometer and estimate the concentration of bacteria in a urine sample to be 4.6 x…

A: dilution factor  =10^-6

Q: One hundred microliters (0.100 ml) of a 10-5 dilution of a bacterial suspension plated on an agar…

A: Colonies of bacteria live on solid media. A colony is characterized as a detectable microorganism…

Q: A plaque assay is performed beginning with 1 mL of a solution containing bacteriophages. This…

A: Concentration is the term used to define the amount of a substance present in the solution or the…

Q: What is the DNA concentration (ug/ml) of an undiluted sample with A260 reading without background of…

A: Pure DNA molecule is extracted by measuring the absorbance of DNA molecule at 260 nm. Pure DNA shows…

Q: According to these images and your own knowledge, can you make a biological drawing of bacteria in…

A: Yoghurt is a nutrient which is rich in lactobacillus (lactic acid bacteria) . Convert milk into…

Scientific Notation

We have to deal with quantities that are extremely large or very small. For example- I may have 6,500,000,000 red blood cells, or the diameter of an iron atom is 0.000000011 inches. Numbers with many zeros can be inexpedient to work with, so scientists use scientific notation. It represents very large numbers or very small numbers in a simple form. We know that whole numbers can be extended to infinity, but we cannot write such large numbers on paper. Numbers that present in millions of places after the decimal point need to be represented simply. Thus, it is difficult to represent a few numbers in their extended form. Therefore, we use scientific notation.