I belive it's a mixture of cartilage and lung tissue containing cila.
To increase surface area for gas exchange.
A bronchiole has no cartilage in its wall, a bronchus does.
Primary bronchiole, secondary and tertiary bronchiole
Nostrils → Nasal Cavity → Pharynx → Larynx → Trachea → Main Bronchus → Lobar Bronchiole → Segmental Bronchus → Bronchiole → Terminal Bronchiole → Respiratory Bronchiole → Alveolar Duct → Atrium → Alveolus
terminal bronchiole, respiratory bronchiole, alveolar duct
Bronchiole is the medical term meaning small bronchi
The parts are the Trachea,Bronchiole,Bronchiole Tubes, Bronchi, and the air sacs.
A air sac
hole, mole,
the cateye
Alveoli.
innermost chamber of respiratory system into which air can be drawn is . Bronchiole