6/1/20202.2: The Respiratory Tract Histology: Essential Human Anatomy and Physiology I with Lab- Kassner1/52.2: The Respiratory Tract HistologyHistology of the LungsHistologyis the study of the cellular anatomy of a tissue or organ that can be viewed through amicroscope. The typicalrespiratory epithelium(or lining of the respiratory tract) is primarily made ofciliated, pseudostratified, columnar cells (seeFigure 2.14andFigure 2.15). These cells have smallcilia(small hair-like projections) at the apex or top of the cells (apical side.) These cilia move or“beat” in an upward sweeping motion. Their action helps to keep the respiratory tract free of debris.The cells are called “pseudostratified” because they appear to be in layers. Upon closerexamination, all the cells attach to thebasement membraneor “floor” of the epithelial tissue. Thecells are calledcolumnarbecause they are taller than they are wide.Goblet cells(mucus producingcells) are also present within the epithelium of the respiratory tract. Goblet cells are named for theirwineglass (or goblet) like appearance. Their mucus helps to trap debris within the respiratory tract,which can then be more easily removed by the cilia.13:03
