Bones are both strong enough to support our weight and light enough to allow us to move. They protect delicate internal organs and store important minerals. Bones come together to form joints, most of which are in constant motion. Muscles make up almost half the weight of the human body. Skeletal muscles work together with bones to provide the power that enables us to move.
Tendons attach muscles to bones, and ligaments surround joints and connect one bone to another.
The ends of bones are covered with cartilage, a smooth, tough, protective tissue that acts as a shock absorber and reduces friction. We also include the skin here the largest organ of the body which acts as a protective barrier to the outside world. Skin also helps to regulate body temperature, senses painful and pleasant stimuli, and shields us from the sun s harmful effects. The most well-known musculoskeletal problems are osteoarthritis, rheumatoid arthritis, and osteoporosis problems which affect thousands around the world. Skin disorders include the minor problems of dry or thin skin, boils, and blisters, as well as more troubling conditions such as psoriasis and eczema.