Search results
Results from the WOW.Com Content Network
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.
The iris consists of two layers: the front pigmented fibrovascular layer known as a stroma and, behind the stroma, pigmented epithelial cells.. The stroma is connected to a sphincter muscle (sphincter pupillae), which contracts the pupil in a circular motion, and a set of dilator muscles (dilator pupillae), which pull the iris radially to enlarge the pupil, pulling it in folds.
The iris dilator muscle (pupil dilator muscle, pupillary dilator, radial muscle of iris, radiating fibers), is a smooth muscle [2] of the eye, running radially in the iris and therefore fit as a dilator. The pupillary dilator consists of a spokelike arrangement of modified contractile cells called myoepithelial cells.
The pupillary sphincter muscle and pupillary dilator muscle control the iris to adjust the size of the pupil to adjust how much light enters into the eye. The pupillary dilator muscle increases the pupillary diameter and it is arranged radially, but the pupillary sphincter muscle is responsible for the constriction of the pupil's diameter and ...
Structure of the iris and surrounding parts showing the stroma of iris (stroma iridis). The stroma connects to a sphincter muscle ( sphincter pupillae ), which contracts the pupil in a circular motion, and a set of dilator muscles ( dilator pupillae ) which pull the iris radially to enlarge the pupil, pulling it in folds.
Rhubarb is a vegetable high in fiber. "[Rhubarb is] rich in fiber, so it really helps with digestion. [It] has a pretty good source of fiber per serving," Wright told Fox News Digital.
There are two types of muscle that control the size of the iris: the iris sphincter, composed of circularly arranged muscle fibers, and the iris dilator, composed of radially arranged muscle fibers. The sphincter is controlled by nerves of the parasympathetic nervous system , and the dilator by the sympathetic nervous system .
A cup of cooked butternut squash contains just 82 calories, and offers about 6.5 grams of fiber, 2 grams of protein, and essential nutrients like iron, potassium and magnesium.