Pseudostratified columnar epithelium is a type of tissue found in various parts of the body, particularly in the respiratory tract. It appears to be layered due to the varying heights of its cells, but all cells are attached to the basement membrane, making it a single layer. This tissue often contains cilia and goblet cells, which help in trapping and moving mucus and debris out of the airways. This type of epithelium plays a crucial role in protecting the respiratory system. The cilia beat in a coordinated manner to push mucus towards the throat, where it can be swallowed or expelled. Pseudostratified columnar epithelium is essential for maintaining clear air passages and preventing infections.