Branching generations of bronchi of the lungs (100X)

This image is showing 3 bronchioles, many alveoli and a few arteries. There are approximately 21 generations of bronchial branches. The first seven generations are made up of bronchi with cartilage and glands in the wall. The last 14 generations are called bronchioles and do not have cartilage or glands in the wall like the ones in this image. The last seven branches belong to the respiratory part because alveoli are found within the wall itself.