Bronchi
The bronchi are the main passage for air to get to the lungs. The right bronchi is shorter than the left bronchi. Smooth muscle tissue helps regulate the air going through the bronchi. The bronchi also use cilia hair and mucus to trap dust and bacteria. The bronchi are made out of cartilage and muscle.
Bronchi are the two main branches.
Bronchioles
Bronchioles are the smaller tubes that give air to the alveoli. Bronchioles are not made out of cartilage, but only smooth muscle. This gives them more flexibility when giving oxygen to alveoli. The bronchioles also have cilia hairs and mucus to trap dust and bacteria.
The bronchioles bring air to the alveoli.