embryonic axis

em·bry·on·ic ax·is

the cephalocaudal axis established in the embryo by the primitive streak.
References in periodicals archive ?
The embryo of species of the Arecaceae family is formed by a single cotyledon, generally little differentiated, and the embryonic axis is in its proximal region.
The gastrulation stage ends when the blastoderm completely covers the yolk, characterizing the 100% epiboly stage, which is marked by the presence of primary germ layers (endoderm, mesoderm and ectoderm) and the embryonic axis, giving rise to the subsequent stage characterized by organogenesis (Wolpert et al.
Thus, we observe that fate allocation is relatively plastic in the evolution of sea urchin embryos, as also indicated by the inconstant relationship between cleavage plane and embryonic axis observed among species with planktotrophic larvae (Henry et al.
Conjoined twinning arises when the twinning event occurs at about the primitive streak stage of development at about 13-14 days after fertilization (2,3), Conjoined twinning occurs by the incomplete splitting of the embryonic axis and, with the exception of parasitic conjoined twins, all are symmetrical and "the same parts are always united to the same parts".
Temperature may also favor the production of growth promoting hormones and enzymes in the embryonic axis.
Neurological features depend on the severity of the malformation and on the segmental level along the longitudinal embryonic axis, the degree of resulting kyphosis and the presence of associated abnormalities.
In introductory biology courses, soaked corn "seeds" (yes, caryopses) are longitudinally bisected along the embryonic axis (the white "shield").
The longest of the 24 articles propose that mitochondrial decline and mtDNA damage are central to the etiology of age-related diseases, and review the genetic control of embryonic axis formation in zebrafish.
The seeds were cut into two portions with a razor blade, and the portion of the seed that lacked the embryonic axis was used for fatty ester analysis.
In situ hybridization, immunocytochemistry, confocal immunoflourescent microscopy, and Southern blotting demonstrated the presence of gamma tubulin, [alpha]-tubulin, EF1[alpha], and several RNAs homologous to Xenopus RNAs implicated in embryonic axis formation or germ cell determination.