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Figure 5

Hox genes in the fruit fly. (a) The set of Hox genes are found in the same order on a chromosome as the order in which they are expressed from anterior to posterior in the embryonic and adult fly. (b) The effects of expressing the Antennapedia gene in a segment anterior to its natural position: wt is a normal fly, and antp is the mutant, with legs (found in the natural Antennapedia segment) growing from the head. (c) Expression of Ultrabithorax posterior to its normal position produces an extra pair of wings on the fly.

Hox genes in the fruit fly. (a) The set of Hox genes are found in the same order on a chromosome as the order in which they are expressed from anterior to posterior in the embryonic and adult fly. (b) The effects of expressing the Antennapedia gene in a segment anterior to its natural position: wt is a normal fly, and antp is the mutant, with legs (found in the natural Antennapedia segment) growing from the head. (c) Expression of Ultrabithorax posterior to its normal position produces an extra pair of wings on the fly.