Question

How does germs,dust,smoke and other chemicals enter into the lungs and cause infection?

Answer 1

Answer:

They enter into the lungs when we inhale oxygen . They come along with oxygen

Answer 2

Answer:

over lungs is covered by a cell called cilia , cilia help mucus to move upward and out into the throat , where it is either coughed up and spat out. Air reaches to alveoli (small air sacs of lungs)  in the inner part of the lungs with any dust particles that avoided the defense in the nose and airways

Explanation: