260 



DAVID W. BISHOP 



Table I. Effect of magnesium concentration on initiation of ATP-induced 

 motility in bull sperm models" 



Mg ++ Molar Concentration 

 Extraction Medium Reactivation Medium 



Reaction Time 

 (seconds) 



6 X 10- 3 

 4 X 10~ 3 

 2 X 10- 3 

 None added 

 4 X 10- 3 



4 X 10- 3 



4 X 10" 3 



4 X 10~ 3 



4 X 1Q- 3 



2 X 10- 3 



<2-10 

 15-30 

 45-70 

 56-18* 



>110 



Data from Bishop and Hoffmann-Be rling, 1959. 



HISTIDINE 



Fig. 6. Flagellation rate of sperm models of sea urchin (Q) and starfish 

 (#) at different concentrations of histidine; 1 mM ATP, 5 mM Mg++, 

 pH 7.5. (After Kinoshita, 1958.) 



