, 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.
New Orleans is one of the oldest cities in America, boasting a storied 300-year history unlike any. other city in the country. The Louisiana Purchase, which doubled the size of the fledgling United. States in 1803, was made for the primary purpose of securing the city of New Orleans and its. port. The transfer was made between France and the United States on December 3, 1803 in the. Cabildo on Jackson Square â one of Americaâs most historic buildings. Today, New Orleans has.