The trabecular meshwork and Schlemm's canal originate from which embryonic tissue?

• A. Neural crest-derived mesenchyme
• B. Surface ectoderm
• C. Mesoderm
• D. Endoderm

Answer: (A)

The opening of the eye’s drainage pathway—the trabecular meshwork and Schlemm's canal—comes from neural crest-derived mesenchyme. During development, neural crest cells migrate into the developing anterior chamber and differentiate into the connective tissue and endothelial components that form these outflow structures. This is different from surface ectoderm, which forms the corneal epithelium and lens, and from other germ layers that don’t contribute these particular anterior-segment drainage tissues. So, neural crest-derived mesenchyme best explains their origin.