If antibodies to fibronectin are exposed to an embryo through which neural crest cells are migrating

Neural crest cell movements are inhibited.

Explanation:

Neural crest cells may be defined as the temporary group of cells that are unique for the chordata group. These cells arise from the embryonic ectoderm and give rise to future melanocytes.

Antibodies to fibronectin association is helpful to study the signalling factors. If these anitodies to fibronectin is shown in the embryonical stage. The neural crest migration is inhibited by its exposure to fibronectin and this might hinder the embryonic development.

Thus, the answer is neural crest cell movements are inhibited.

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