Final answer:
In the growth of cartilage, chondrocytes divide and add more matrix between the existing cells through a process known as Interstitial growth, which is essential for the elongation of long bones during development.
Step-by-step explanation:
In the growth of cartilage, chondrocytes divide and add more matrix between the existing cells, and this type of growth is called Interstitial growth. During interstitial growth, new cartilage is formed within the existing cartilage, causing it to expand from within. This process is essential in the elongation of long bones during the developmental stages of life.
Appositional growth, on the other hand, refers to the increase in the diameter of bones by the addition of bone tissue at the surface. Endochondral ossification is the process of bone development from hyaline cartilage where a bone lengthens as chondrocytes secrete more matrix. In this context, however, when focusing on how chondrocytes directly contribute to the expansion of cartilage itself, it is interstitial growth that is being described.