The human musculoskeletal system is the organ system that gives humans the ability to physically move, by using the muscles and skeletal system. It consists of the muscular system and the human skeleton. Bones are connected to each other at the joints by ligaments or cartilage and skeletal muscle is attached to bones, usually by tendons.  «Bones
Bone is a constantly changing tissue that has several functions. Bones serve as rigid structures to the body and as shields to protect delicate internal organs. They provide housing for the bone marrow, where the blood cells are formed. Bones also maintain the body's reservoir of calcium. In children, some bones have areas called growth plates. Bones lengthen in these areas until the person reaches full height, at which time the growth plates close. Thereafter, bones grow very slowly - in thickness far more than in length. «Joints
Bones come together to form joints. The configuration of a joint determines the degree and direction of possible motion. Some joints do not move, except in very young children (during and for a short time after birth). Examples of such joints are those located between the plates of the skull. Other joints allow a large and complex range of motion. For example, the shoulder joints, which have a ball-and-socket design, allow inward and outward rotation as well as forward, backward, and sideways motion of the arms. Hinge joints in the elbows, fingers, and toes allow only bending (flexion) and straightening (extension). «Ligaments
Ligaments are tough fibrous cords, composed of connective tissue that contains both collagen and some elastic fibers. The elastic fibers allow the ligaments to stretch to some extent. Ligaments surround joints and bind them together; they help strengthen and stabilize joints, permitting movement only in certain directions. Ligaments also connect one bone to another. «Muscles
There are three types of muscles: skeletal, smooth,...