Which two layers of the iris are derived from mesoderm?

The stroma and the anterior limiting layer of the iris are indeed derived from mesodermal tissue. The stroma is the connective tissue that provides structure and contains blood vessels, nerves, and melanocytes, which contribute to the iris's pigmentation. This layer is critical for the physiological and functional properties of the iris, including its role in controlling the amount of light entering the eye.

The anterior limiting layer, which is a thin structure on the front of the iris, is primarily made up of fibrous connective tissue and reinforces the iris's shape. Both layers originate from the mesoderm, which is one of the three primary germ layers formed during embryonic development and gives rise to various tissues and structures in the body, including connective tissue, muscle, and blood vessels.

Understanding the developmental origins of ocular structures is essential for comprehending their anatomy and function, which is crucial in the context of optometry and ophthalmology. The other options involve layers that are primarily derived from ectoderm, such as the iris epithelium, thereby reinforcing the importance of correctly distinguishing between the germ layer origins of different parts of the iris.