Animals are cut from a cloth woven largely of collagen. This rope-like protein is the most abundant in the body, giving structure to tissues such as skin and cartilage, but to date chemists haven't fully understood the source of collagen's strength. A prevailing theory dictated that the molecule-a tightly wound triple helix-was braced by a scaffolding of water molecules. But research from the University of Wisconsin-Madison points to a different answer, one that not only helps explain collagen's properties, but also might eventually expand the protein's utility in cosmetic surgery, wound healing and perhaps even arthritis diagnosis and treatment.

Select from the choices above to read the entire article.