Muscles move different body parts and limbs by contacting and relaxing. The skeleton works as a structure for your body and provides protection for your organs. Sensory organs are the organs of the body that help us become conscious and respond to our surroundings.
Muscles move body parts by contracting and then relaxing. Muscles can pull bones, but they can't push them back to the original position. So they work in pairs of flexors and extensors. The flexor contracts to bend a limb at a joint.
