The publication of uncle tom cabin written by harriet beecher stowe contribute to the start of the civil war by

The book was written as a criticism of slavery.  With the passage of the Fugitive Slave Act in 1850, people in the north were required to return slaves to the south by law or they would be arrested.  Uncle Tom's Cabin made people in the north feel badly for the terrible conditions of the slaves and not want to comply with the Fugitive Slave Act.

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 hope helps you