296 



ADVENTURES IN RADIOISOTOPE RESEARCH 



RESULTS 



Eggs incubated for 6—18 days. The results of the determination of the 

 specific activities (activities per mgm P) of the different fractions 

 extracted from seven embryos and from the remaining parts of eggs 

 incubated for 11 days are shown in Table 2, while Tables 3—5 give 

 the results obtained with eggs incubated for 18, 16 and 6 days. In 

 addition to the specific activity (activity per mgm P, with that of the P 

 extracted from the white of the egg taken as 100), we have also recorded 

 in Tables 2 and 3 the activity (in counts per minute or in % of amount 

 injected) and the P content of the fraction — this last quantity being 

 determined, in all cases, by the method of Fiske and Subbarrov^. 



Ta ble 2. — Specific Activity of P Extracted from Different Fractions of an 

 Egg Incubated for 11 Days. (Specific Activity of P Extracted from the 



White Taken as 100) 



Fraction 



Counts 

 per min 



Specific 

 activity 



Embryo: Average acid-soluble P 



Inorganic P 



Adenosine-P -|- inorganic P . . 



Creatine-P 



Phosphatide-P 



Residual ("nucleoprotein") P 

 Yolk: Phosphatide-P 



0.074 

 0.077 

 0.121 

 0.171 

 0.561 

 1.49 

 10.4 



Table 3. — Specific Activity of P Extracted from Different Fractions of an 

 Egg Incttbated for 18 Days. (Specific Activity of P Extracted from the White 



Taken as 100) 



Fraction 



I 



mgm P 



% of amount 

 injected 



Embryo: Average acid-soluble P 



Inorganic (without skeleton) P 



Tibia and femur-P 



Adenosine-P 



Phosphatlde-P 



Residual ("nucleoprotein") P . . 

 Yolk: Acid-soluble P 



Phosphatide-P 



Residual P 



19.7 

 10.91 

 4.50 

 0.048 

 1.08 

 0.204 

 0.828 

 17.50 

 2.16 



53.5 

 27.2 

 7.6 

 0.14 

 1.7 

 0.3 

 1.3 

 0.28 

 0.12 



Specific 

 activity 



19 



17 



11 



20 



11 



10 



11 

 0.11 

 0.40 



The figures for the specific activities (activities per mgm P) of different 

 fractions extracted from an embryo and from the remaining parts of an 

 egg incubated for 18 days are shown in Table 3. The P content in mgm, 



