How is the bronchi not an organ?

The bronchi are not considered an organ because they are part of the respiratory system's airway structure rather than a distinct, functional unit with specific physiological roles. Organs are typically defined as collections of tissues that work together to perform particular functions, while the bronchi primarily serve as passageways for air to move to and from the lungs. Instead, they are classified as tubular structures, part of the overall anatomical framework that supports respiratory function.