<P> The iris sphincter muscle ( pupillary sphincter , pupillary constrictor , circular muscle of iris , circular fibers ) is a muscle in the part of the eye called the iris . It encircles the pupil of the iris , appropriate to its function as a constrictor of the pupil . </P>
<P> The iris sphincter muscle ( pupillary sphincter , pupillary constrictor , circular muscle of iris , circular fibers ) is a muscle in the part of the eye called the iris . It encircles the pupil of the iris , appropriate to its function as a constrictor of the pupil . </P>
what type of muscle is in the iris
what type of muscle is in the iris
sphincter
sphincter