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A mass of undifferentiated protoplasm capable of growth and differentiation.



in the study of regeneration, the accumulation of homogeneous, nonspecialized cells on the surface of a wound after amputation of an organ. Tissues of the organ that is being restored are formed from blastemas in the course of regeneration.

In embryology: (1) a group of cells from which a new individual develops by asexual reproduction in some multicellular animals (Coelenterata, worms, Ascidia, and others); (2) the surface layer of cytoplasm in the cen-trolecithal ova of many arthropods. By means of fine outgrowths the blastema is connected to the cytoplasm, which surrounds the nucleus situated in the center of the ovum.

References in periodicals archive ?
A year ago, Dr Mark Keating, who studies regeneration in zebra fish (which can re-grow fins, scales, spinal cord and part of its heart), identified a gene essential for initiating blastema formation when the fish's tail fin is cut.
For some reason, people and other nonurodele vertebrates lack this ability to create a blastema.
The researchers found that the fish uses a special genetic trick that allows the acid to control the formation of blastema, which means the animal is able to produce a store of cells that can rebuild the fin.
30-32) During nephrogenesis, PAX-2 appears very early in the renal blastema and promotes mesenchymal cell proliferation and apoptosis, and mesenchymal-epithelial transformation, with formation of immature renal tubules and glomeruli.
Unlike mammals, which heal wounds by forming a scar, these mice begin by forming a blastema, a structure associated with rapid cell growth.
Adult Wilms tumor is a triphasic neoplasm composed of a mixture of blastema, epithelium, and/or stroma.
Washington, March 27 (ANI): Scientists at the Pentagon have completed the first phase of their plan to regrow soldiers' limbs, by turning human skin into the equivalent of a blastema - a mass of undifferentiated cells that can develop into new body parts.
The latter postulate followed the delineation by Kupffer, (30) Huber, (22) and Brodel (23) of the dual role of the ampullary bud and renal blastema in renal nephrogenesis.