Page 243 - Atlas of Histology with Functional Correlations

Medium magnification.

FIGURE 7.3 | Hyaline Cartilage and Surrounding

Structures: Trachea

This illustration depicts a hyaline cartilage plate from the trachea. The

perichondrium (5) with fibroblasts (7) surrounds the cartilage. The inner
chondrogenic layer (4) produces chondroblasts (8) that differentiate into
chondrocytes. Chondrocytes in lacunae appear either single or in isogenous

groups (3). Lacunae and chondrocytes (3) in the middle of the cartilage plate are
large and spherical but become flatter toward the periphery, where these cells are
differentiating into chondroblasts (8). The interterritorial (intercellular)
matrix (1) stains lighter, whereas the territorial matrix (2) around the lacunae
stains darker.

Vascular (9) connective tissue (10) and tracheal glands with grapelike
secretory units called acini are near the cartilage. Serous acini (11) produce
watery secretions, whereas mucous acini (12) secrete lubricating mucus. An
excretory duct (6) delivers these secretions to the tracheal lumen.

FIGURE 7.3 ■ Hyaline cartilage and surrounding structures: trachea. Stain:

hematoxylin and eosin. Medium magnification.

FUNCTIONAL CORRELATIONS 7.1 ■ Cartilage

Cells

Cartilage develops from mesenchymal cells that differentiate into

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