sentences:  Mainly, the lamellipodium increase in size and extend numerous filopodia in order to collect as much sensory information as possible.The role of pioneer axons in neuronal development has been studied extensively in various invertebrate and vertebrate systems in both the central nervous system and peripheral nervous system.Although these experiments have shed light on the functions of the pioneer axons, the results reveal conflicting information into the extent of the effect of pioneer axons on proper development.