Lesson 3 – What body parts enable movement, support, respiration, and circulation? - We learned that some animals have an exoskeleton to help protect them from being eaten. As they grow they shed the old exoskeleton and underneath is a new one. The bones do the following: support the body, anchor muscles, protect internal organs, store minerals such as calcium, and make blood cells. We also learned that the muscular system is responsible for movement in our body. The three types of muscle are cardiac as in the heart, skeletal that pulls on our bones to help us move, and smooth muscle that makes up the walls of blood vessels and organs.