Answer:
At the tip of each bronchiole is Alveoli.
Step-by-step explanation:
In respiratory system Bronchiole are an important part. They function as a passage for the transport of air coming from the nose and mouth towards alveoli. Smooth muscles present in Bronchiole control the air flow by contraction and relaxation. At the tip of each Bronchiole air sacs called Alveoli are present. The function of alveoli is to exchange oxygen and carbon dioxide to and from blood.