Answer:
molecule enter a cekk by passing through the cell membrane
When the air pressure within the alveolar spaces falls below atmospheric pressure, air enters the lungs (inspiration), provided the larynx is open; when the air pressure within the alveoli exceeds atmospheric pressure, air is blown from the lungs (expiration).
Answer:
I'm sorry. I wanted to try and answer the question but I can't because it isn't clear.
