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E. S. GUZMAN BARRON 



Figure 4. Effect of iodoacetate on the O2 uptake of sea urchin sperm. Abscissa, time 

 in minutes. Ordinate, O- uptake in mm^. (i) Control (heavy suspension). (2) Heavy- 

 suspension with iodoacetate (o.ooiM). (3) Control (dilute suspension). (4) Dilute 

 suspension with iodoacetate (o.ooiM). 



