many alterations in shape, size, staining properties, and structure in different disease
processes. An adult female has approximately 4.8 million/cu mm red cells, and an adult
male has approximately 5.4 million/cu mm red cells. The erythrocytes have an average
life span of 80 to 120 days. See Table 1-1 for purposes of the blood cell tree as
described in this subcourse.
Table 1-1. Blood cell tree.
b. Leukocytes. Leukocytes are commonly known as white blood cells because
of their lack of color in unstained preparations. They are nucleated cells that have an
average diameter of 8 to 12 microns. There are 5,000-10,000 leukocytes per cubic
millimeter of blood. Leukocytes are divided into three groups: (1) granulocytes
(neutrophils, eosinophils, and basohils) that can phagocytose or ingest bacteria or other
particles; (2) lymphocytes which participate in humoral (B lymphocyte) and cell
mediated (T lymphocyte) immunity and (3) monocytes that phagocytose bacteria
cellular debris and interact with lymphocytes in the processing of antigens in the
immune reaction. In humans, there are 3 types of phagocytes: macrophages,
granulocytes, and monocytes. All three types are attracted to bacteria and certain other
particles by substances released by the particles (the process of chemotaxis). They
then pin the particle against a surface and engulf it. They are differentiated by the
specific nuclear and cytoplasmic staining properties.
c. Thrombocytes. Thrombocytes are found commonly known as platelets.
They are the morphologically recognizable precursors of platelets and are detached