Page 70 - Atlas of Histology with Functional Correlations

Careful examination of this figure shows how individual tubular structures can

change shape and appearance, depending on the plane of section through the
tubules. Similar structural alteration is possible in solid structures, such as the
muscle fibers, connective tissue fibers, or nerve fibers.

FIGURE 1.11 ■ Planes of section through a hollow object, a tube.

FIGURE 1.12 | Hollow Tubules of the Testis in

Different Planes of Section

Organs such as the testes and kidneys consist primarily of highly twisted or

convoluted tubules. When flat sections of such organs are seen on a histology
slide, the cut tubules exhibit a variety of shapes because of the plane of section.
To show how twisted tubules appear in a histologic slide, a portion of a testis
was prepared for examination. Each testis consists of numerous, highly twisted

seminiferous tubules that are lined by multilayered or stratified germinal
epithelium.

A longitudinal plane (1) through a seminiferous tubule produces an
elongated tubule with a long lumen. A transverse plane (2) through a single
seminiferous tubule produces a round tubule. Similarly, a transverse plane

through a curve (3, 5) of a seminiferous tubule produces two oval structures
that are connected by solid layers of cells. An oblique plane (4) through a tubule
produces an oval structure with an oval lumen in the center and multiple cell

layers at the periphery. A tangential plane (6) of a seminiferous tubule passes
through its periphery. As a result, this plane produces a solid, multicellular, oval

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