What is the process called when cartilage is replaced by bone?

The correct term for the process when cartilage is replaced by bone is ossification. Ossification, also known as osteogenesis, is a critical biological process that occurs during the development of the skeletal system. It involves the transformation of cartilage into bone tissue, which is vital during the growth of long bones in the body and also plays a significant role in the healing of fractures.

During ossification, specialized cells called osteoblasts synthesize new bone matrix, which gradually replaces the cartilage. This process not only contributes to the formation of bone but also ensures the structural integrity of the skeletal system as an individual grows and matures.

In contrast, calcification refers specifically to the accumulation of calcium salts in body tissues, which can occur in various contexts, not limited to the conversion of cartilage to bone. Osmosis is a distinct physiological process involving the movement of water across a semi-permeable membrane and does not relate to bone formation. Cancellous formation typically refers to the development of spongy bone inside the body and is not synonymous with ossification. Thus, ossification precisely captures the process of cartilage being transformed into bone.