Matching Pairs Skeletal SystemOnline version Match the following by Ms. Burton 1 The hardness of bones is called ____________ 2 The ribs 3 The spine 4 The skull 5 Bones are made out of ? Made up of vertebrate that support and protect the spinal cord. Different kinds of tissues/ Crystals of Calcium Protects the brain and forms the shape of the face. Protect the heart, lungs, and other organs in the chest cavity.