Blood

Blood Components:

Find a region in the blood smear specimen where the RBC's are separated (not overlapping). When studying the blood smear specimen, pay close attention to nuclear characteristics, staining patterns, and cell diameter (remember that erythrocytes are usually 7-8 mm in diameter).

Peripheral blood smear, Wright's stain.
Identify the following components:
Erythrocytes (red blood cells; RBC’s)
Note the paler-staining centers of the cells, which is indicative of the biconcave shape of the cells.
Platelets
These are small blue-purple clusters interspersed among the blood cells.

Leukocytes
Leukocytes (or White Blood Cells) can be divided into two main types: Agranular & Granular. When studying the WBC's, keep in mind the percentages listed below which represent the normal adult leukocyte differential.

Agranular Leukocytes
Monocytes
Look for fibrillar chromatin in the nucleus and abundant light blue cytoplasm. The nucleus is eccentrically located, and the nuclei of larger monocytes are often indented. Recall that macrophages arise from monocytes.
Lymphocytes
Look for clumped chromatin in the nucleus and a thin rim of basophilic cytoplasm. The nucleus is generally round and dark, is generally centrally located, and nuclear diameter is often about the same as the RBC cell diameter.

Granular Leukocytes
Neutrophils
These are the most common WBC. Look for multilobed nuclei, individual granules are not distinguishable. The cytoplasm is lightly stained and has a slightly granulated appearance (in contrast to the agranular leukocyte cytoplasm).
Eosinophils
Look for bilobed nuclei, individual granules are distinguishable and eosinophilic (stain intensely red-orange).
Basophils
These cells are very rare in the blood. Basophils have coarse, basophilic granules that usually obscure the nucleus. They are not easily distinguished in this preparation.