Primary 5 have been learning about the RESPIRATORY SYSTEM. Our lungs are not the only thing responsible for our breathing. Healthy lungs can inhale and exhale clearly because our bronchioles and alveoli are clear and wide to exchange OXYGEN for CO2 gas. Some one who suffers an asthma attack can’t breathe properly because their bronchioles and alveoli become narrow and restricted. We used balloons and straws to show this condition.