In thickness, the bone grows due to cell division of the inner layer of the periosteum. Bone growth in length is carried out due to growth plates (zones), which are located closer to the ends of the bones. Here, the cartilage tissue is continuously growing and replaced by bone tissue. If this layer of cartilage is ossified, then bone growth stops (this happens, as a rule, by the age of 18-20).
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.