Formula Sheet - BI107 1st Lab Practical
Microscope
Magnification
Calculating the Diameter of the Field of View at Other Magnifications
Known magnification
------------------------------- X original um = Diameter of
Unknown magnification
field of View
um
Averages of Diameter of Field of View
Estimate of an object under the microscope
Approach you would take to estimate the size of a microscopic object, if you are given the
diameter of field of views at different magnifications.
Step 1: Focus on the object at certain magnification and note the diameter of the field of view at
that magnification.
Step 2: Determine (guesstimate) the percent of the diameter of the field of view is occupied by
the object (image).
Step 3: Use the following formula…..
Percent
Object Size = --------------------- X =
100
Diameter of
field of view um
Diffusion and Osmosis
Final weight (g) - Initial Wright (g)
Initial Wright (g)
X 100 =
NOTE: This could be a negative value because your bag is losing water.
%
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Calculation of Rate of Metabolism
mL O2
-------- X 60 = #
minutes

#
--------------------- =
Weight of gerbil
ml O2/hr/gram
Note: You have to subtract the total weigh of the cage from the gerbil, so you could get the gerbil’s
actual weight.
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Effect of Light Intensity on the Rate of Photosynthesis
.1
X 60 =
Elapsed Time
ml O2/hr
Note: The numerator is always going to be .1
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Paper Chromatography
Note: cm or mm, depending on your professor, but the KEY POINT… If you get a number
that’s higher than “1.” You got the wrong answer. Flip the numbers and you should get the right
answer.
Another way is to divide the smaller number by the bigger number.