Final answer:
Endochondral ossification involves the formation of a cartilage template, its vascularization, ossification, and the remodeling of the newly formed bone tissue. The correct sequence for the process aligns with option A: Formation of cartilage template, ossification, vascular invasion, and bone remodeling.
Step-by-step explanation:
The major steps in the process of endochondral ossification are:
- Mesenchymal cells differentiate into chondrocytes, which form the cartilage model of the future bony skeleton.
- The perichondrium develops around the cartilage model and eventually transforms into the periosteum, while a periosteal collar develops around the diaphysis.
- Capillaries penetrate the cartilage, leading to the formation of a primary ossification center within the diaphysis where bone tissue starts to replace cartilage.
- As the bone continues to develop, cartilage and chondrocytes keep growing at the ends of the bone, while ossification also progresses in these areas, forming secondary ossification centers in the epiphyses.
- Cartilage remains within the growth (epiphyseal) plate and at the joint surface as articular cartilage, which is important for bone lengthening and joint function.
The correct sequence for the major steps is Formation of cartilage template, ossification, vascular invasion, bone remodeling, which corresponds to option A. During this process, bony tissue such as osteocytes, osteoblasts, osteoclasts, and osteoprogenitor cells play vital roles in the conversion of the hyaline cartilage model into bone.