Final answer:
The skeletal system constitutes about 20% of an adult's body mass and serves multiple critical functions, including support, movement, and protection of vital organs like the heart, lungs, and brain. It is also involved in the renewal process, with 10% of skeletal mass being regenerated each year.
Step-by-step explanation:
The skeletal system is a vital component of the human body, as it provides an internal framework that supports the body and allows for movement. The system includes all of the bones, cartilages, and ligaments that make up the body's structure. In adults, the skeletal system accounts for approximately 20% of body mass. This system has several key functions, including protecting vital organs such as the heart and lungs, which are shielded by the rib cage, and the brain, which is encased in the skull. The bones of the skeletal system also play a crucial role in maintaining stability and enabling mobility, with different parts specialized for various functions, such as the lower skeleton for stability during walking or running and the upper skeleton designed for greater mobility.
Regarding the renewal of skeletal mass, it is estimated that each year about 10 percent of an adult's skeletal mass is broken down and rebuilt, which allows the bones to maintain their strength and function over time.