Abstract
The author has ascertained the manifestation of the phosphorylase activity during the embryonic development in the silkworm by determining the liberated P, the disappeared 10'P, that is hydrolyzable P compounds in N HCl at 100°C for 10 minutes, and the glucose formed in the experimental conditions.
The activity showed such varieties during the incubation at 25°C as following: After the hydrochloric acid treatment for the artificial hatching preceding the incubation, it declined and was kept at constant low level until around the blastokinesis, followed with rapid arise and reaching the maximum at the period just before the head pigmentation and then decreasing again. Since this tendency was antagonistic against that of the glycogen content, the author assumed that phosphorylase played an active role in the glycogen metabolism in this insect.
Two forms of glycogen, free and fixed, were also detected as shown by KEMP et al (10) in mammalian tissues. Phosphorylase may be concerned in the free glycogen, because the free glycogen varies in its content in proportion with change in the enzyme activity, whilest the fixed glycogen does not.
