Fig. 2.

[Ca²⁺]_i in phasic and tonic growth cones as a function of time during depolarization with medium containing 60 mm K⁺. The [Ca²⁺]_i goes higher in phasic growth cones than in tonic growth cones. Mean values were obtained from 19 phasic growth cones from eight animals and 22 tonic growth cones from eight animals.