(1) Acrochordons, or skin tags, are derived from ectoderm and mesoderm and represent a hyperplastic epidermis.(2) Why is the origin of mesoderm from hypoblast in some groups not regarded as a secondary adaptation?(3) The stem cells for hematopoiesis in mammals are derived from mesoderm in the yolk sac blood islands and a region of the aorta.(4) Crystal cells constitute a class of hemocytes derived from the head mesoderm .(5) The cells of the visceral mesoderm and dorsal vessel also express both genes.(6) Expression is also detected variously in visceral endoderm, and anterior mesoderm and endoderm of the gut and pharynx in some vertebrates and amphioxus.(7) We have used experimental manipulation of chick embryos to test the causal role of Hox genes in patterning derivatives of the paraxial mesoderm .(8) Cells from the ventrolateral dermomyotome migrate away from the midline forming a population of axially derived cells that differentiate within the lateral mesoderm .(9) Derived from embryonic mesoderm , mesenchyme is the first connective tissue formed.(10) Endoderm and mesoderm form from the lower layer of cells.(11) Because neoblasts are likely derived from embryonic stem cells, a stem cell system may be even the original mode of mesoderm formation in the embryo.(12) Teratoma typically contains tissues derived from all 3 germinal layers, whereas dermoid cyst presumably originates from ectoderm and mesoderm .(13) The stem cell lines also retain the ability, throughout the culture, to differentiate into tissue-derived endoderm, mesoderm and ectoderm.(14) Clearly the establishment of independent Hox codes in the paraxial and lateral plate mesoderm would have significance for both the development and the evolution of vertebrates.(15) By the time segmentation is complete, strong mxp expression is detected in both ectoderm and mesoderm of the maxillary and labial limb buds.(16) The most affected tissue being dorsal mesoderm ; the notochord is disrupted and the tailbud fails to form.
