Figure 6.

The last four granule motions before fusion. The motions of 159 granules before fusion were determined. (A and B) The z motions are shown during intervals -4 and -2, and during intervals -3 and -1, respectively, before exocytosis. Motions toward the glass interface are negative. Motions are shown for which one or both of the pair has or have greater than a 95% probability of not being accounted for by instrumental noise (see Appendix). Both measurements were at greater than 95% confidence intervals for 63 and 62 granules in A and B, respectively. (C and D) The R motions are shown during intervals -4 and -2, and during intervals -3 and -1, respectively, before exocytosis. All R motions were statistically significant at the 95% confidence interval.