The initial configuration of a complete, three-dimensional finite element model, based on available geometric, fabric, and mechanical-property data, is shown in Fig. 12. Each finite element represents a triangular patch of approximately 150 cells. The finite element engine was used to determine how the tissues in the model embryo would interact with each other over time. The engine shows that the neural tube of the model embryo does indeed roll up (Fig. 12b-f) and that it does so in a manner that is similar to neural tube closure in real embryos.
Sensitivity analyses showed that morphogenetic movements are highly sensitive to details of the initial configuration and tissue mechanical properties, a finding consistent with previous 2D simulations [Clausi and Brodland, 1994].