normoblast

(redirected from Orthochromatic normoblast)
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Related to Orthochromatic normoblast: Basophilic normoblast, polychromatophilic erythroblast, Polychromatic Erythroblast, Polychromatic normoblast, Polychromatophilic erythrocyte, Erythroblasts

normoblast

 [nor´mo-blast]
a nucleated precursor cell in the erythrocytic series, specifically one in a normal course of erythrocyte maturation, as opposed to a megaloblast. The four developmental stages of the series are called pronormoblasts or proerythroblasts, basophilic normoblasts or erythroblasts, polychromatophilic (or polychromatic) normoblasts or erythroblasts, and orthochromatic normoblasts or erythroblasts. adj., adj normoblas´tic.

nor·mo·blast

(nōr'mō-blast),
A nucleated red blood cell, the immediate precursor of a normal erythrocyte in humans. Its four stages of development are: 1) pronormoblast, 2) basophilic normoblast, 3) polychromatic normoblast, and 4) orthochromatic normoblast See: erythroblast.
[normo- + G. blastos, sprout, germ]

normoblast

/nor·mo·blast/ (nor´mo-blast)
2. term now often used as a synonym of erythroblast; sometimes more specifically, a nucleated cell in the normal course of erythrocyte maturation, as opposed to a megaloblast. When used in the latter sense, the four developmental stages of the nucleated cells of the erythrocytic series are usually named pronormoblasts (proerythroblasts) and basophilic, polychromatophilic, and orthochromatic normoblasts (see under erythroblast). normoblas´tic

normoblast

[nôr′məblast]
Etymology: L, norma + Gk, blastos, germ
nucleated bone marrow red blood cell precursor. Developmental stages include the pronormoblast, the basophilic normoblast, the polychromatophilic normoblast, and the orthochromic normoblast. After the extrusion of the nucleus of the normoblast, the young erythrocyte becomes known as a reticulocyte and enters the circulating blood. Compare erythrocyte. See also reticulocyte. normoblastic, adj.
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Basophilic normoblast

nor·mo·blast

(nōr'mō-blast)
A nucleated red blood cell, the immediate precursor of a normal erythrocyte in humans. Its four stages of development are: 1) pronormoblast, 2) basophilic normoblast, 3) polychromatic normoblast, and 4) orthochromatic normoblast.
See also: erythroblast
[normo- + G. blastos, sprout, germ]

normoblast

A nucleated red blood cell precursor showing the features of normal red cell development, as distinct from those of the MEGALOBLAST.

normoblast

immature (nucleated) erythrocyte precursor

nor·mo·blast

(nōr'mō-blast)
A nucleated red blood cell, the immediate precursor of a normal erythrocyte in humans.
[normo- + G. blastos, sprout, germ]

normoblast (nôr´mōblast),

n a nucleated red blood cell found in the peripheral bloodstream in severe pernicious anemia and in some leukemias.

normoblast

a nucleated precursor cell in the erythrocytic series; metarubricyte.
Four developmental stages are recognized: the pronormoblast (prorubricyte); the basophilic normoblast (basophilic rubricyte, erythroblast), in which the cytoplasm is basophilic, the nucleus is large with clumped chromatin, and the nucleoli have disappeared; the polychromatic normoblast (polychromatic erythroblast, rubricyte), in which the nuclear chromatin shows increased clumping and the cytoplasm begins to acquire hemoglobin and takes on an acidophilic tint; and the orthochromatic normoblast (acidophilic normoblast, metarubricyte, orthochromatic erythroblast), the final stage before nuclear loss, in which the nucleus is small and ultimately becomes a blue-black homogeneous structureless mass.