The Maryland Society for Promoting the Abolition of Slavery and the Relief of Free Negroes and Others Unlawfully Held in Bondage was founded in 1789, the same year the former colonies replaced their Articles of Confederation with the new Constitution, âin order to form a more perfect union.â.
In humans and other mammals, respiratory gas exchange or ventilation is carried out by mechanisms of the lungs. The actual exchange of gases occurs in the alveoli. Note: The above text is excerpted from the Wikipedia article Gas exchange, which has been released under the GNU Free Documentation License.
The smallest bronchioles end in tiny air sacs, called alveoli, which inflate during inhalation, and deflate during exhalation. Gas exchange is the delivery of oxygen from the lungs to the bloodstream, and the elimination of carbon dioxide from the bloodstream to the lungs. It occurs in the lungs between the alveoli and a network of tiny blood vessels called capillaries, which are located in the walls of the alveoli.