What are the detailed lines in an iris?

Stroma: The stroma is the outermost layer of the iris and is made up of loose connective tissue, blood vessels, nerves, and pigment cells called melanocytes. The stroma is responsible for giving the iris its color.

Fibrous layer: The fibrous layer is located beneath the stroma and is made up of dense connective tissue. It helps to support the iris and maintain its shape.

Collagenous layer: The collagenous layer is located beneath the fibrous layer and is made up of collagen fibers. It helps to further support the iris and prevent it from tearing.

Epithelium: The epithelium is the innermost layer of the iris and is made up of a single layer of pigmented epithelial cells. The epithelium helps to protect the iris from damage.

Crypts of Fuchs: The crypts of Fuchs are small depressions in the epithelium that contain stem cells. These stem cells can differentiate into new epithelial cells, which helps to repair damage to the iris.

Pupil: The pupil is the central opening in the iris that allows light to enter the eye. The pupil is surrounded by the sphincter pupillae muscle, which controls the size of the pupil.

Iris sphincter: The iris sphincter muscle is a circular muscle that surrounds the pupil. It is responsible for constricting the pupil, which helps to reduce the amount of light that enters the eye.

Iris dilator: The iris dilator muscle is a radial muscle that is located on the back of the iris. It is responsible for dilating the pupil, which helps to increase the amount of light that enters the eye.