Fig. 6. Contraction force and kinetics of ovipositor muscle 271 obtained from immature (<5 day), mature (>14 day, sham-op.) and allatectomised females (–CA). (A) Examples of muscle contractions from immature (left) and mature females (right), showing considerably increased forces and altered kinetics. (B) Quantification of forces exerted during twitch and tetanus (50 Hz) contractions. The twitch/tetanus ratios for all groups are shown. (C) Contraction and relaxation kinetics of single twitches. Muscles from mature females contract and relax significantly faster than those of immature and allatectomised females. Data are means ± S.D.; ^*P<0.05; ^**P<0.01;^***P<0.001.