, Physiologist. 1  In four chambered avian and mammalian hearts, the two upper chambers are known as the atria. The atria are believed to act as primer pumps which boost the end diastolic volume (the volume at the end of ventricular filling) just before contraction of the ventricles.
Disunion follows the Civil War as it unfolded. New Orleans was the jewel of the Confederacy. In addition to being the Southâs largest city, it boasted considerable industry that produced ironclads, munitions and uniforms, among other items. More important, it controlled access to the Mississippi River from the Gulf of Mexico.
Origins of New Orleans. New Orleans is called the Crescent City because the original town-the Vieux CarrÃ©, also called the French Quarter-was built at a sharp bend in the Mississippi River. The town was founded about 1718 by Jean Baptiste Le Moyne, Sieur de Bienville.