Pupillary reflex is synonymous with pupillary response, which may be pupillary constriction or dilation. Pulmonary shunting is minimized by the normal reflex constriction of pulmonary vasculature to hypoxia. Both of these medications activate alpha-1 adrenergic receptors that result in smooth muscle constriction. The inhaled form may result in constriction of the bronchioles. Physostigmine also has a miotic function, causing pupillary constriction. A throttle is the mechanism by which fluid flow is managed by constriction or obstruction. This is also the case when the arterial constriction and collateral circulation are bilateral. Gradient, constriction, and obstruction are streambed topography factors and are relatively consistent. Blood flow is blocked by constriction and blood clots (thrombosis). Another term for the constriction of the pupil is miosis. The esophagus has four points of constriction. The opposite, constriction of the pupil, is referred to as miosis. This process is known as apical constriction. This figure is helpful in identification of glottal and ventricular constriction. These are produced from the neck by mitotic growth, which is followed by transverse constriction.