Answer: Collagen
Collagen is the protein that holds together the different structures of the body, including skin and bones. This is because the collagen molecule has the ability to mix with many types of substances and minerals, and in the case of bone tissue, the combination of collagen with calcium crystals allows the formation of the hard and rigid structure necessary for healthy bones.
Note that this component is the most abundant in mammals, especially in their skin, and in the specific case of humans, corresponds to approximately
of the total mass of proteins in our body.