Page 65 - Atlas of Histology with Functional Correlations

FIGURE 1.9 ■ Small artery and veins showing blood cells and the surrounding

connective tissues.

INTERPRETATION OF HISTOLOGIC

SECTIONS

One of the biggest challenges histology students encounter is interpreting what

the two-dimensional histology sections represent in three dimensions. Histologic
sections are thin, flat slices of fixed and stained tissues or organs mounted on
flat glass slides. Such sections are normally composed of cellular, fibrous, and
tubular structures that are cut in different planes. As a result, a variety of shapes,

sizes, and layers may be visible, depending on the plane of section. Fibrous
structures are solid and are found in connective, nervous, and muscle tissues.
Tubular structures are hollow and represent various types of blood vessels,
lymph vessels, glandular ducts, and glands of the body.

In tissues and organs, the cells, fibers, and tubes have a random orientation

in space and are parts of a three-dimensional structure. During the preparation of
histology slides, the thin sections cut from the specimen do not show much
depth. In addition, the plane of section does not always bisect these structures in

exact transverse or cross section. As a result, this produces a variation in the

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