Most small-molecule neurotransmitters are stored in small vesicles that range from 40 to 60 nm in diameter and, in electron micrographs, appear to have clear centers. The vesicles that store neuropeptides are larger, ranging from 90 to 250 nm in diameter.
The world's largest concentration of natural sandstone arches. 1  Hike the 1.5 mile trail leading to the base of Delicate Arch to experience one of the most breathtaking vistas in the world. 2  Your family will love the short trails in the Windows Section that lead right up to several massive arches.
One of the reliefs on the underside of the arch. Housed at the Arc, is the French tomb of an unknown soldier and the eternal. flame dedicated to all fallen soldiers from World War I and World War II. The long climb up 284 steps to the top of the Arc de Triomphe is well worth it. At the top of the stairs is a small museum that tells the story of the Arc's construction. Take a look at the displays before making your way to the exit leading to the top platform.