GENERAL HISTOLOGY

Detailed explanation-1: -The zone of calcified matrix, the zone closest to the diaphysis, contains chondrocytes that are dead because the matrix around them has calcified. Capillaries and osteoblasts from the diaphysis penetrate this zone.

Detailed explanation-2: -In the hypertrophic zone of the growth plate, the chondrocytes die as a result of apoptosis or other processes, leaving behind a calcified matrix that consists of deteriorating collagen fibres intermingled with large clumps of aggrecan and the glycosaminoglycan hyaluronan.

Detailed explanation-3: -During endochondral ossification, chondrocytes proliferate, undergo hypertrophy and die; the cartilage extracellular matrix they construct is then invaded by blood vessels, osteoclasts, bone marrow cells and osteoblasts, the last of which deposit bone on remnants of cartilage matrix.