Abstract
We have quantitatively determined the variations of the liver alkaline glycerophosphatase rate during and after ontogenesis. The glycerophosphatase rate of plasma, of embryonic extract and of the medium employed for the culture of chick organ primordia were also determined. This investigation shows an initial diminution of the enzymic rate from the 4th to the 6th incubation day and an increase after hatching. We have observed that the glycerophosphatase activity of the medium is higher than that of the sum of single activities of plasma and embryonic extract. This fact emphasizes the importance of the composition of the medium in research on alkaline glycerophosphatase activity in vitro.