Figure 6­42
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Holdings,
Several cells in the development of erythrocytes and leukocytes are depicted in this electron micrograph of bone
LLC.
marrow. The two cells labeled with the arrows are polychromatophilic normoblasts. Their large, centrally located
nuclei and abundant heterochromatin are characteristic. These cells have few organelles. The cell with the smallest
Not
nucleus and the most heterochromatin is an orthochromatic normoblast (arrowhead). The nucleus is placed to one
to
side of the cell and will soon be extruded. Portions of two mature erythrocytes (E) and a myelocyte (M) are also
be
redistributed
visible in this image. (Micrograph courtesy of Ann Bretschneider, Robert Wood Johnson Medical School)
or
modified
in
any
way
without
permission.
293

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