Answers:1.      False. Basic gas-exchange unit of the respiratory system is the alveoli.2.      True3.      False. In the Main stream bronchi, the right is more vertical.4.      True5.      True6.      True7.      False. Neural control of respirations is located in the medulla.8.      False. The respiratory center in the medulla is stimulated by the concentration of carbon dioxide in the blood.9