Humans are in a group of animals called vertebrates. The ability of the human body to move in many ways is attributable to complex jointing, or articulation. Joints are where two bones meet and movement occurs. Muscles power the movement of the body. Muscles attach across joints to move bones.
Muscles attach to bones with tissue called tendons.
Ligaments are tissues that connect bone to bone and can provide guides for tendons. Pairs of antagonistic muscles contract to provide movement. A stimulus is something that excites a nervous impulse. A response is an action that happens as a result of a stimulus. The smooth, predictable action of bones, muscles, and central nervous system is called coordination.