Abstract:PHYSIOLOGYand the method of extraction, and by two to correct for the 50 % loss due to the geometry of the counter, we get 1200 disintegrations per minute.This is equal to 5.4 x 1j7 mc, since 1 mc = 2...PHYSIOLOGYand the method of extraction, and by two to correct for the 50 % loss due to the geometry of the counter, we get 1200 disintegrations per minute.This is equal to 5.4 x 1j7 mc, since 1 mc = 2.22 x 109 disintegrations per minute.Inserting the specific activity (797 mc/gm) of the Fe55 used, the 5.4 x 10 7mc becomes equivalent to 6.8 x 10-7 mg Fe55 as the amount in our sample of 500 mg of dried root material.This quan- tity could not be measured by chemical methods. SUMMARYA method has been presented whereby dried plant material is wet ashed and the contained radioactive Fe55 converted to a ferric thiocyanate complex, which is then taken up in isoamyl alcohol.After evapora- tion of aliquots of the isoamyl alcohol on sample pans the count is made in a gas-flow counter.Read More