Tracheal epithelium. Coloured freeze-fracture transmission electron micrograph (TEM) of the lining of the trachea, or windpipe. At upper centre is a g

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Tracheal epithelium. Coloured freeze-fracture transmission electron micrograph (TEM) of the lining of the trachea, or windpipe. At upper centre is a goblet cell (purple) which produces mucus (green) which lines the inner walls of the trachea. This mucus traps microorganisms and other airborne irritants and prevents them entering the lungs. To the left and right of the goblet cell are ciliated epithelial cells, with long, finger- like projections (cilia). These cilia rhythmically waft mucus away from the lungs, up the trachea and towards the throat where it can be swallowed or coughed up. Magnification unknown.

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Size: 5178px × 3388px
Photo credit: © J. L. CARSON, CUSTOM MEDICAL STOCK PHOTO/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: anatomy, body, cell, cilia, epithelium, goblet, human, mucus-secreting, respiratory, system, trachea, tracheal, windpipe