Flowering plant serve to protect the sporophylls and to form an envelope attractive to pollinators. The individual members of these surrounding structures are known as sepals and petals (or tepals in flowers such as "Magnolia" where sepals and petals are not distinguishable from each other). The outer series (calyx of sepals) is usually green and leaf-like, and functions to protect the rest of the flower, especially the bud. The inner series (corolla of petals) is, in general, white or brightly colored, and is more delicate in structure. It functions to attract insect or bird pollinators. Attraction is effected by color, scent, and
Renal calyx volume that stretches the walls of the calyces. This causes them to fire impulses which stimulate rhythmical contraction and relaxation, called peristalsis. Parasympathetic innervation enhances the peristalsis while sympathetic innervation inhibits it. A "staghorn calculus" is a kidney stone that may extend into the renal calyces. A renal diverticulum is diverticulum of renal calyces. Renal calyx The renal calyces are chambers of the kidney through which urine passes. The minor calyces surround the apex of the renal pyramids. Urine formed in the kidney passes through a renal papilla at the apex into the minor calyx; two or three minor calyces