This part displays 'normal' morphology of different cell lineages. Normal in a sense that the cells dispayed are not dysplastic. This does not mean that the presence of these cells in the peripheral blood, like blasts, is normal. In addition a large number of morphologically normal cells may still be abnormal.
Although subtle differences exists between cells and their maturation states, some rules of thumb may be applied to assess a cells age. Think of the structure and size of the nucleus, the color of the cytoplasm and the ratio between the nucleus and the cytoplasm.
Young cells exhibit a fine chromatine structure that, as the nucleus matures, evolves into a coarser pattern with white stains. The subsequent phase is complete condensation during which the nucleus clumps together and ultimately fragments (apoptosis).
Cytoplasm tends to become lighter in color as the cell matures. This can be seen in particular with neutrophilic granulocytes, erythrocytes and monocytes. Lymphocytes are an exception in this regard, considering that mature, resting lymhpocytes generally have scant darkblue cytoplasm. In addition, cellular activity can also make the cytoplasm darker (for example in plasmacytoid lymphocytes).
Immature cells have a big nucleus that spans a relatively large part of the entire cell. During maturation, the size of the nucleus goes down, making more of the cytoplasm visible. Again, lymphocytes are an exception; in general, resting lymphocytes have barely visible cytoplasm.