Which structure is a muscular and glandular tissue at the peripheral base of the iris and produces aqueous humor?

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Multiple Choice

Which structure is a muscular and glandular tissue at the peripheral base of the iris and produces aqueous humor?

The structure described is the ciliary body, a tissue that is both muscular and glandular located at the peripheral base of the iris. It contains the ciliary muscle, which changes the lens shape for focusing, and the ciliary processes that secrete aqueous humor. This clear fluid fills the eye’s anterior chamber, nourishing avascular structures like the lens and cornea and helping to maintain intraocular pressure. That dual role of movement for accommodation and secretion of fluid is what defines this structure. Conjunctiva is a mucous membrane covering the sclera and inner eyelids, not involved in fluid production. The cornea is the transparent front surface of the eye that focuses light but does not secrete aqueous humor. Endothelium is an inner cell layer lining surfaces such as the cornea and blood vessels, not muscular and glandular, and it does not produce aqueous humor.

The structure described is the ciliary body, a tissue that is both muscular and glandular located at the peripheral base of the iris. It contains the ciliary muscle, which changes the lens shape for focusing, and the ciliary processes that secrete aqueous humor. This clear fluid fills the eye’s anterior chamber, nourishing avascular structures like the lens and cornea and helping to maintain intraocular pressure. That dual role of movement for accommodation and secretion of fluid is what defines this structure.

Conjunctiva is a mucous membrane covering the sclera and inner eyelids, not involved in fluid production. The cornea is the transparent front surface of the eye that focuses light but does not secrete aqueous humor. Endothelium is an inner cell layer lining surfaces such as the cornea and blood vessels, not muscular and glandular, and it does not produce aqueous humor.

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