Fig. 3. Effect of loss-of-function mutations in  nmr-1 and  glr-1 on xenon action on time moving backward.  Box plots of percentage of time moving backward in air and in 70% xenon for wild-type worms (N2),  N -methyl-d-aspartate receptor null mutant (  nmr-1(ak4) ), non–  N -methyl-d-aspartate receptor null mutant (  glr-1(ky176) ), rescued  glr-1(ky176) , the  nmr-1(ak4);glr-1(ky176) double mutant, and the volatile anesthetic resistant mutant  unc-64(md130) . The  box extends from the 25th to 75th percentile (  lower and  upper bars ); the  middle line represents the median, and the  whiskers represent the range from lowest to highest value. n > 10 animals for all conditions. * Statistically different from air,  P < 0.05, two-tailed, unpaired  t test.