Page 803 - Atlas of Histology with Functional Correlations

FIGURE 20.7 | Cross Section of Seminiferous

Tubules Showing Supportive Sertoli Cells,

Spermatogonia, and Spermatids in Different

Stages of Development

This higher-magnification photomicrograph shows in greater detail the cells in
and around the seminiferous tubules. In the central tubule, the germinal

epithelium exhibits the largest cells, the primary spermatocytes (3). In the right
tubule are the developing early spermatids (10) with dense, round nuclei. The
central tubule contains the elongated and dense-staining nuclei of late
spermatids (6) with their tails extending into the lumen of the seminiferous
tubule (5). At the base of the germinal epithelium are the dark type A (4) and

pale type A spermatogonia (7). Also visible are the very distinct Sertoli cells
(9, 12) with oval nucleus and a characteristic dense-staining nucleolus. Sertoli
cell cytoplasm extends from the base of the germinal epithelium to the lumen of

the seminiferous tubule (5). Embedded within the Sertoli cell (9, 12) cytoplasm
are the developing spermatocytes (3) and spermatids (6, 10). Surrounding the
seminiferous tubules is a basement membrane (11) and the flattened fibrocytes
(8). Located also between the seminiferous tubules are the testosterone-secreting
interstitial cells (of Leydig) (1, 13), some of which are located adjacent to a

capillary (2).

FIGURE 20.7 ■ Cross section of seminiferous tubules showing supportive
Sertoli cells, spermatogonia, and spermatids in different stages of development.

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