Some zonular fibers are present in the anterior vitreous and can be observed by electron microscopy. However, most of these fibers form the zonular apparatus, which is the structural connection between the lens and the ciliary body. The major structural protein of these fibers is a large linear protein named fibrillin, which has an unusually high cysteine content.
Excerpted from BCSC 2020-2021 series: Section 2 - Fundamentals and Principles of Ophthalmology. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.