# Metabolism Based Calculations

How do you calculate specific activity, total activity, and % radioactivity given the information in the attachment?

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...pecific activity in DPM/mole.

% of radioactive x - A percentage of the number of molecules of substance x that are radioactive.

In your case, you have 32 moles of glucose (C6O6H12) that has been radioactively labelled at carbons 1, 2, 4, and 5 with C-14, a radioactive isotope of carbon. Each C-14 has an activity of 84 DPM, for a total activity of 420 DPM.

The 32 moles of glucose will be metabolised by glycolysis and completely oxidized by the citric acid cycle. You must trace the radioactivity through the various cycles.

Here are a few examples:

(8): We know that all of the carbons will eventually end up as carbon dioxide. Since 4 out of 6 initial carbons were radioactively labelled, it follows that 4 ...