Question

почему.несмотря на то что рост кости в толщину осуществляется непрерывно за счёт надкостницы,кость взрослого человека не становится массивнее

Answer 1

В костях есть особые клетки-остеокласты,которые разрушают старую ткань кости,что приводит к ее обновлению.То есть параллельно идут процессы разрушения старой ткани и ее обновление новыми клетками.

 

Answer 2

Стенки костномозговой полости содержит клетки, растворяющие кость. Достигается оптимальная прочность кости при наименьшей массе и затрате материала

Answer 3

Why doesn't the bone of an adult become thicker despite continuous growth in thickness due to periosteum?

The bone of an adult does not become thicker despite continuous growth in thickness due to the periosteum because the process of bone remodeling balances bone formation and resorption. Bone remodeling is a dynamic process that involves the continuous breakdown and rebuilding of bone tissue throughout a person's life. This process is regulated by various factors, including mechanical stress, hormones, and cytokines.

Bone Formation and Resorption: Bone remodeling involves two main processes: bone formation and bone resorption. Osteoblasts are responsible for bone formation, while osteoclasts are responsible for bone resorption. Osteoblasts lay down new bone tissue, while osteoclasts break down old or damaged bone tissue. These processes work together to maintain bone health and integrity.

Balance between Bone Formation and Resorption: The balance between bone formation and resorption is crucial for maintaining bone strength and structure. If bone resorption exceeds bone formation, it can lead to bone loss and conditions like osteoporosis. On the other hand, if bone formation exceeds resorption, it can lead to excessive bone growth and conditions like osteopetrosis.

Regulation of Bone Remodeling: Bone remodeling is regulated by various factors, including mechanical stress, hormones, and cytokines. Mechanical stress, such as weight-bearing exercise, stimulates bone formation by activating osteoblasts. Hormones like estrogen and testosterone also play a role in bone remodeling. Estrogen, for example, helps maintain bone density in women. Cytokines, which are signaling molecules, regulate the activity of osteoblasts and osteoclasts.

Conclusion: In summary, the bone of an adult does not become thicker despite continuous growth in thickness due to the periosteum because bone remodeling maintains a balance between bone