The tertiary bronchi (also known as the segmental bronchi) arise from the secondary bronchi. The respiratory epithelium lining their lumen is surrounded by a layer of smooth muscle. This layer is composed of two ribbons of smooth muscle that spiral in opposite directions. The smooth muscle layer is surrounded by irregular plates of hyaline cartilage which help maintain the patency of the airway. Secondary bronchi (also known as lobar bronchi) arise from the primary bronchi, with each one serving as the airway to a specific lobe of the lung. ... Smooth muscle is a type of non-striated muscle, found within the walls of hollow organs; such as blood vessels, bladders, uteri. ... Cartilage is type of dense connective tissue. ...
Each of the tertiary bronchi serves a specific bronchopulmonary segment. There are 10 bronchopulmonary segments per lung, each of which is separated from the others by a layer of connective tissue. This means that each bronchopulmonary segment is a discrete anatomical and functional unit, and this separation mean that a bronchopulmonary segment can be surgically removed without affecting the function of the other segments. The tertiary bronchi get smaller and divide into primary bronchioles. The human lungs are the human organs of respiration. ... Connective tissue is any type of biological tissue with an extensive extracellular matrix and often serves to support, bind together, and protect organs. ... The primary bronchioles arise from the tertiary bronchi. ...
References
Gartner, Leslie P. and James L. Hiatt. Color Textbook of Histology, 2nd ed. (2001). ISBN 0-7216-8806-3
Human tertiarybronchus was incubated overnight at 4°C in
was primarily observed in the epithelial cell layer of the tertiary
Data are shown as the mean ± SEM of seven preparations from four donors, under each experimental condition, and are expressed as a percentage of the relaxation to isoprenaline (1 µM).
Pulmonary artery (secondary, tertiary and quaternary generation), primary pulmonary vein, trachea and bronchus (primary, secondary and tertiary generation) were removed and cleaned of adherent tissue.
Strips (approximately two cartilage rings width; 5−7 mm length) were cut from the trachea and primary bronchus, and rings (approximately 2−5 mm diameter, 3−4 mm length) were cut from the secondary and tertiary bronchi.
A similar gradation in the maximum response to the endothelin receptor ligand, sarafotoxin S6c, was noted from upper tracheal to bronchial tissue of the guinea-pig (Hay et al., 1993).
Feeds |
Contact