Body plan

Schneuwly, S., Klemenz, R and Gehring, W. J. (1987). Redesigning the body plan of Drosophila by ectopic expression of the homeotic gene Antennapedia. Nature 325 816-818. ... 

In the ways described above, only the genes required at a given moment are expressed. This not only helps to conserve the energy of the cell, but also is critical for correct cellular differentiation, tissue pattern formation and formation of the body plan. 

Homeotic gene a gene responsible for encoding a part of the body plan. 

Geneticists discovered in D. melanogaster and other species genes that establish the placement of antennae and legs on particular segments and in general to specify the body plan.470 471 These homeotic genes... 

The shapes and body plans of animals vary enormously. Consequently, the study of embryonic development of sea urchins, insects, frogs, chickens, mice, and humans might appear to lead to quite unrelated conclusions. However, there are many similarities as well as variety. 

Limb patterning is important with respect to how the precise arrangement of structures is generated within the limb but the pattern of limb initiation is also central to the body plan (reviewed Cohn and Tickle, 1996). What ensures that limbs develop in the proper positions and that the type of limb is appropriate to that position ... 

Cohn, M. Tickle, C. (1996). Limbs a model for pattern formation within the vertebrate body plan. Trends Genet. 12(7), 253-257. 

De Robertis EM, Oliver G, Wright CVE. Homeobox genes and the vertebrate body plan. Scientific American 1990 46. 

Fig. 12.3. This drawing transmits a realistic concept of the time of development of metazoa as a function of the total biogenic time on earth. Notice how short the distance is between a jellyfish and a human and how little time there was in the old model to convert any of these established species into a completely different body plan. The Genomic Potential Hypothesis gives each species an almost equally long time of development during the Archean period.

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