MITOTIC INHIBITION INDUCED IN GRASSHOPPER NEUROBLASTS BY EXPOSURE TO OZONE
Technical documentary rept.
GEORGIA INST OF TECH ATLANTA
Pagination or Media Count:
Living neuroblasts of the grasshopper Chortophaga viridifaciata were exposed to ozone. The threshold dose necessary to produce a significant delay in mitosis was determined. Inhibition was reversible and mitosis, though delayed, went to completion. Cells dosed before early prophase were inhibited and differed from the controls in the time taken to reach anaphase. Cells in more advanced stages proceeded to anaphase at a time not significantly different from the controls. Cells exposed in anaphase, telophase, interphase, and very early prophase were delayed in passing through midprophase and late prophase stages. Progression through preceding and succeeding stages was the same as control preparations. Exposure to ozone in the preprophase stages resulted in inhibition in late prophase, and cells exposed in later stages proceeded through the next cell division uninhibited. Stages sensitive to the threshold concentration of ozone are preprophase, and the inhibited stages are middle and late prophase.
- Anatomy and Physiology