Mydriasis iris sphincter, composed of circularly arranged muscle fibers, and the iris dilator, composed of radially arranged muscle fibers. The sphincter is innervated by (signaled by nerves of) the parasympathetic nervous system, and the dilator by the sympathetic nervous system. Sympathetic stimulation of the adrenergic receptors causes the contraction of the radial muscle and subsequent dilation of the pupil. Conversely, parasympathetic stimulation causes contraction of the circular muscle and constriction of the pupil. The mechanism of mydriasis depends on the agent being used. It usually involves either a disruption of the parasympathetic nerve supply to the eye (which normally constricts the
What a Man My Man Is (album) Anderson's husband at the time, Glenn Sutton, produced this album and wrote a couple of its tracks, including the No. 1 hit. What a Man My Man Is (album) What a Man My Man Is is the name of a studio album by country singer Lynn Anderson, released in late 1974. The album was named after Anderson's big hit, "What a Man My Man Is," which hit No. 1 on the country charts in the last week of 1974. The song would be her last No. 1 hit and last entry on the pop music Hot 100 chart. This album