Question

Explain how bone remodeling maintains normal bone integrity for adults

Answer 1

Much of the cellular activity in a bone consists of removal and replacement at the same site is called process remodeling. The remodeling process occurs throughout life and becomes dominant by the time that bone reaches its peak mass and remodeling continues throughout life so that most of the adult skeleton is replaced about every 10 years.

Where as during childhood and adolescence bones are sculpted by a process called modelling, which allows for the formation of new bone at one site and the removal of old bone from another site within the same bone. This process allows individual bones to grow in size and to shift in space.

Both genes and the environment contribute to bone health. Some elements of bone health are determined largely by genes, and errors in signaling by these genes can result in birth defects. External factors, such as diet and physical activity, are critically important to bone health throughout life, and these factors can be modified.

The growth of the skeleton, its response to mechanical forces, and its role as a mineral storehouse are all dependent on the proper functioning of a number of systemic or circulating hormones that respond to changes in blood calcium and phosphorus. If calcium or phosphorus are in short supply, the regulating hormones take them out of the bone to serve vital functions in other systems of the body. Too many withdrawals can weaken the bone.