Which type of ossification involves the transformation of cartilage into bone?

Endochondral ossification is the process by which cartilage is transformed into bone, which is fundamental for the development of long bones and most skeletal structures in the human body. This process begins with a hyaline cartilage model that is gradually replaced by bone tissue. It typically involves several stages including the formation of a cartilage template, calcification of the cartilage, invasion of blood vessels, and the eventual formation of bone by osteoblasts.

During endochondral ossification, chondrocytes in the cartilage model undergo hypertrophy and apoptosis, paving the way for bone tissue to take its place. This process is vital during fetal development and through adolescence, contributing to the growth of long bones until they reach their mature size. It contrasts with intramembranous ossification, which does not involve a cartilaginous phase and tends to occur in flat bones like the skull. Understanding this distinction highlights the critical role that endochondral ossification plays in skeletal development and growth. Thus, the correct answer is indeed associated with the transformation of cartilage into bone.