19.5: Pattern Formation
- Page ID
- 74614
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- 19.5.2: Segmentation
- Insects, like all arthropods, are segmented. The body of Drosophila melanogaster is built from 14 segments, but what signals guide segment formation? The process begins with the gradients of messenger RNA (mRNA) that the mother deposited in her egg before it was fertilized. Shortly after fertilization, these are translated into their proteins with a gradient of bicoid diminishing from anterior to posterior and a gradient of nanos diminishing from posterior to anterior.