How will you describe the pathway of oxygen in the breathing system?

Air enters through the nose or mouth (which join to form the nasopharyngeal cavity). The air travels through the trachea which and the trachea splits into two bronchi. The air travels through the bronchi which split into smaller and smaller bronchioles. The tiny bronchioles and the air ends up in the miniscule alveoli, where the oxygen in the air diffuse into the bloodstream. Carbon dioxide diffuse from the bloodstream into the alveoli and the unwanted gas travels in reverse back to the nose and mouth, where it is breathed out.

1. why does the same side of the moon always face earthc.the rotational period of the moon is equal to one revolution around earth2. which is greater the moons period of rotation or its period of revolution  b.the moons revolution period around earth3.what was the major accomplishment of the apollo missions  c.sending the first human into space4. which of these space missions involved the deployment of lunar roversa. voyager 15. which scientists are going to explore next on kepler-186fd. evidence of existence of life6.which mission is not going to explore the outside of the solar  systemb.safir7.which technology limit the future of space explorationb. scientist must first develop certain technologies before missions can be completed.