Describe the changes that happen to the bones, muscles, and joints as a person ages and what a person can do about it.

With age, people lose bone density or mass, mainly women post-menopause. The bones lose essential minerals like calcium. The spine is formed of the bones known as vertebrae, the vertebrae also lose mineral constituents to some extent, making each bone thinner. The spinal column becomes compressed and gets curved. The long bones of the legs and arms become more brittle due to mineral loss.  

The joints turn less flexible and stiffer, the concentration of fluids in the joints may get reduce. The cartilage may start to rub against each other and wear away, and the phenomenon of calcification may take place in some of the joints like in the shoulder.  

Lean body mass reduces primarily because of the loss of muscle tissue. With age, fat, and lipofuscin, that is, an age-related pigment gets deposited in the tissues of the muscles. The muscle fibers get shrink and get substituted more gradually. The lost tissues of the muscle get substituted with hard fibrous tissue. The muscles become less toned and possess less tendency to contract due to the modifications in the muscle tissue and usual aging variations in the nervous system.  

In order to overcome or prevent the issues with the joints, muscles, and bones, exercise is one of the best ways. A moderate exercise program can assist one to maintain balance, strength, and flexibility. Exercise assists in keeping the bones strong. Apart from exercise, one should consume a well-balanced diet containing more amount of calcium.  

i think the answer is become an organ donor.