Ciliary muscle

The intrinsic smooth muscle of the ciliary body of eyeball; it consists of circular fibers (fibrae circulares, radial fibers (fibrae radialis, meridional fibers (fibrae meridionales [TA]), and longitudinal fibers (fibrae longitudinales; action, in contracting, its diameter is reduced (like a sphincter's), reducing tensile (stretching) forces on lens, allowing the lens to thicken for near vision (accommodation).

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