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 design of the respiratory system. 1  The human gas-exchanging organ, the lung, is located in the thorax, where its delicate tissues are protected by the bony and muscular thoracic cage. The lung provides the organism with a continuous flow of oxygen and clears the blood of the gaseous waste product, carbon dioxide. Atmospheric air is pumped in and out regularly through a system of pipes, called conducting airways, which join the gas-exchange region with the outside of the body.