Abstract
The variation of active phosphorylase activity and glycogen concentration in the tissues of Philosamia ricini during larval and pupal development were studied. The optimum pH for the active phosphorylase of larval tissue was pH 7.6 at 30°C during a 30min incubation period. The enzyme phosphorylase accumulates during early larval stage, and then declines to a constant level which is maintained till pupation. The U-shaped pattern of variation of this enzyme during larval and pupal development and more or less the reverse pattern from the pupal stage till adult emergence are remarkable. Glycogen increase during this period was due to increased amylase activity and concurrent glyconeogenesis. Variation of the U-shaped pattern of change in glycogen concentration, during metamorphosis appears to be governed by the active phosphorylase activity. The changes observed were discussed in correlation with other metabolic changes.
