Electron microscopic studies on differentiation of the mouse epiphyseal cartilage
Goel, S.C.
Folia Biologica 25(1): 87-95
1977
ISSN/ISBN: 0015-5497 PMID: 852621 Document Number: 122733
Differentiation of the epiphyseal cartilage from toes of the hind limbs of the mouse, was studied by EM. During chondrogenesis, the extracellular phase increases in extent and acquires unbanded, thin collagen fibers and polygonal, electron dense granules; the outline of the cell changes from smooth to scalloped; the nucleocytoplasmic ratio decreases; the nucleus becomes eccentrically located; the general electron density of the cell increases; glycogen accumulates and, most importantly, the cell acquires a well-developed endoplasmic reticulum and Golgi apparatus. Interconvertibility of the various components of the membrane system was observed. The results suggest that the collagen is secreted directly by the endoplasmic reticulum. Feedback control of nuclear activity by the contents of the endoplasmic reticulum is suggested.