7.8 Summary of Section 7
This section has sought to illustrate the formation of connections between neurons and their targets by exploring a few examples. The picture that emerges is one of cells at different stages of development subjected to a vast array of signals. These signals are the medium through which environmental factors exert their effects. To some of these signals, some cells respond; to other signals, other cells respond. What a cell, a neuroblast, a growth cone actually does is dependent on the combination of signals around and receptors it produces. Figure 21 summarises the main types of influences on the growth cone of the axon.

The end result is a marvellously choreographed, precision production.