Tag Archives: graph

Standard curve: A new test on maths4bioscience

A new test has been added to the maths4bioscience website – The Standard Curve.

So what is a “standard curve”?

A “standard curve” is a graph that is generated using known concentrations or amounts of something to produce a reading. The reading could be an absorbance, conductivity, fluorescence, pretty much anything that can be measured. The collected readings are then used to plot a graph of known amount or concentration against the thing that is being measured. This graph is a standard curve, which you can then use to determine the concentration or amount present in an unknown sample.

A very common type of “standard curve” is the protein determination standard curve. In this case, a range of known concentrations of a protein are used, and their absorbances are measured using a spectrophotometer. Plot the absorbances against the protein concentrations, and you have a standard curve. You cane now use the graph to determine the concentration of protein in a solution with a known absorbance.

Using data derived in the lab to plot a standard curve is a key skill for a bioscientist. And the new test allows you to practice your graph plotting and calculation of the unknown concentration of some protein samples.

So what is the “standard curve” test?

The test presents you with a table of data of absorbances for a range of known protein concentrations. You are also given the absorbances of three protein samples of unknown concentrations.

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Using the data, you plot a standard curve. (If you have trouble drawing graphs then have a look at the blog post on How to draw a graph – there is also a graph drawing video on YouTube.)

Graph Drawing Checklist: Get a checklist for graph drawing – Send the Checklist

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And using the standard curve you then determine the protein concentrations of the three unknowns.

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Once you have determined the protein concentrations, and also calculated the extinction coefficient, you enter the data and click mark.

The site will then give you feedback on your answers, including showing you the standard curve for the data. If you get things right then all you see is the graph and the answers.

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If you get any of the answers wrong then you still get the graph, plus an explanation of how to work out the correct answers.

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Graph Drawing Checklist: Get a checklist for graph drawing – Send the Checklist

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The data for the standard curve, along with the absorbances for the three unknowns, is randomly generated and so this means that the site can you provide you with countless questions for you to answer.

If you are struggling with your graph drawing, and getting good data plots, then you might like to take the free Maths and Chemistry Refresher Course we offer at Maths4Biosciences.

If you found this blog post interesting or useful then please share it with your friends and classmates via email, Twitter or Facebook.

How to draw a graph

How to draw a graph

Hand drawing a graph is an essential skill for any science (physics, chemistry, or biology) or maths students. You need to know how to draw a graph by hand before you move on to use a computer program to produce your graphs.

In the above video I will show you the key components required to produce a good graph. These include:

  • making the best use of the graph paper
  • adding the correct labels

In addition, I will also show you how to construct a standard curve using data from a protein assay, and how to use the graph to determine the unknown concentration of a sample.

If you are struggling to draw good graphs then this handy checklist will help you produce good quality graphs:

Graph Drawing Checklist: Get a checklist for graph drawing – Send the Checklist

If you are struggling with your graph drawing, and getting good data plots, then you might like to take the free Maths and Chemistry Refresher Course we offer at Maths4Biosciences.

There is also a slide stack available over at slideshare.net:

 

If you are looking for a way to brush up your ‘science maths’ skills then please visit http://maths4biosciences.com where you will find a wide range of online tools to test your understanding of the maths you need for your biology and chemistry courses.