IN VIVO SYNTHESIS AND BREAKDOWN OF DEOXYRIBONUCLEIC ACID IN TRIBOLIUM CONFUSUM DUVAL

Abstract

The in vivo synthesis of deoxyribonucleic acid (DNA), as shown by the rate of incorporation of14C-thymidine, has been investigated at different stages in the life cycle of Tribolium confusum. During the larval period, a close similarity is observed between the rate of DNA synthesis and the pattern of growth. The pupal stage, which is a non-growth phase, is characterized by a cessation of DNA synthesis. During the larval growth phase, although the 3-day-old larvae have the lowest and the 13-day-old have the highest rate of DNA synthesis, the rate of DNA degradation in the older larvae is almost twice as great as that of the younger larvae. These findings are consistent with the observed total concentration of DNA of the insect at these stages.