Certified Clinical Ophthalmic Assistant (CCOA) Practice Exam

The ciliary body is the structure responsible for producing aqueous humor, which is a clear fluid that fills the anterior chamber of the eye. This fluid is critical for maintaining intraocular pressure, providing nutrients to the avascular structures of the eye, and facilitating the removal of metabolic wastes.

The ciliary body contains specialized cells known as ciliary processes, which actively secrete aqueous humor into the posterior chamber of the eye. From there, the fluid flows through the pupil into the anterior chamber and eventually drains out through the trabecular meshwork and Schlemm's canal.

Understanding the roles of other structures is important, but they do not produce aqueous humor. For instance, the cornea's primary function is to refract light entering the eye, the iris controls the diameter of the pupil and, therefore, the amount of light that enters the eye, while the lens focuses light onto the retina. Each of these components plays a vital role in vision but does not contribute to the production of aqueous humor.