The sclera is made of collagen fibers. Collagen is a protein that is also found in your skin, muscles, bones, and connective tissue. The sclera looks white because of the crisscrossing layers of ...

It's so well constructed. You've got the iris, the cornea, the pupil, and the sclera, are all working together to allow us to see. The eye muscles have to be fast. Just to track an object involves ...