Please help.
Assume that a cell culture has a density of 10^8 cells/mL. You transfer 20 microliters of this culture onto the microscope slide.
A) How many cells do you expect will be in this 20 microliters drop you placed under the microscope?
B) You add to your sample above an equal volume of a liquid dye, India Ink solution. You transfer 20 microliters of this mixture onto a microscope slide. How many cells do you expect will be now on this 20 microliters drop you placed under the microscope?
number cells= density*volume
10^8/ml * 20mmL*1ml/1000mml
= 20*10^5 cells
To answer these questions, we need to consider the dilution factor introduced by transferring a specific volume of the cell culture.
A) To calculate the number of cells in the 20 microliters drop, we need to determine the volume of the original cell culture that was transferred.
Step 1: Calculate the volume of the original cell culture that was transferred.
We know that the density of the cell culture is 10^8 cells/mL, and the volume transferred is 20 microliters. We can use the following formula to calculate the volume transferred in milliliters:
Volume (mL) = Volume (microliters) / 1000
Volume (mL) = 20 / 1000 = 0.02 mL
Step 2: Calculate the number of cells in the 20 microliters drop.
To find the number of cells, we can multiply the volume transferred (in milliliters) by the cell culture density:
Number of cells = Volume (mL) * Density (cells/mL)
Number of cells = 0.02 * 10^8 = 2 * 10^6 cells
So, you would expect there to be 2 million cells in the 20 microliters drop.
B) Now, let's calculate the number of cells in the 20 microliters drop after adding the India Ink solution.
Step 1: Calculate the total volume of the mixture.
When you add 20 microliters of the India Ink solution to the 20 microliters of the cell culture, the final volume of the mixture will be 40 microliters.
Step 2: Calculate the number of cells in the 20 microliters drop of the mixture.
We can use the same formula as before, but this time, the volume transferred is 20 microliters (from the mixture of cell culture and India Ink).
Number of cells = Volume (mL) * Density (cells/mL)
Number of cells = (20/1000) * 10^8 = 2 * 10^6 cells
So, even after adding the India Ink solution, you would still expect there to be approximately 2 million cells in the 20 microliters drop.