The uvea is the eye layer that includes the iris. It is also known as the uveal layer or the vascular tunic. It is the middle layer of the eye and is composed of three parts: the choroid, ciliary body, and the iris. The choroid is a dark brown pigmented layer that supplies blood to the retina. The ciliary body is responsible for controlling the shape of the lens and the production of aqueous humor. The iris is the colored part of the eye that controls the amount of light entering the eye.