MICROANATOMY

Detailed explanation-1: -This process involves the replacement of hyaline cartilage with bone. It begins when mesoderm-derived mesenchymal cells differentiate into chondrocytes. Chondrocytes proliferate rapidly and secrete an extracellular matrix to form the cartilage model for bone.

Detailed explanation-2: -A primary ossification center is the first area of a bone to start ossifying. It usually appears during prenatal development in the central part of each developing bone. In long bones the primary centers occur in the diaphysis/shaft and in irregular bones the primary centers occur usually in the body of the bone.

Detailed explanation-3: -Throughout childhood and adolescence, there remains a thin plate of hyaline cartilage between the diaphysis and epiphysis known as the growth or epiphyseal plate (Figure 6.4. 2f). Eventually, this hyaline cartilage will be removed and replaced by bone to become the epiphyseal line.

Detailed explanation-4: -Epiphyseal cartilage is hyaline cartilage tissue with a gelatinous texture, and it is responsible for the longitudinal growth of the long bones in birds and mammals. It is located between the epiphysis and the diaphysis. Epiphyseal cartilage also is called a growth plate or physis.

Detailed explanation-5: -Long bones have a thick outside layer of compact bone and an inner medullary cavity containing bone marrow. The ends of a long bone contain spongy bone and an epiphyseal line. The epiphyseal line is a remnant of an area that contained hyaline cartilage that grew during childhood to lengthen the bone.