State two adaptations of epithelial cells.

1. Cilia: Some epithelial cells, such as those lining the respiratory tract, have cilia on their surface. Cilia are hair-like structures that help move mucus and other particles along the surface of the epithelium, aiding in the clearance of debris and pathogens from the respiratory tract.

2. Tight junctions: Epithelial cells often have tight junctions, which are specialized protein complexes that form a seal between adjacent cells. This helps to create a barrier that prevents the passage of molecules and pathogens between cells, maintaining the integrity of the epithelial layer and regulating the movement of substances across it.

1. Tight Junctions: These junctions create a physical barrier between neighboring cells, preventing the leakage of substances between cells. This adaptation is crucial for maintaining tissue integrity and preventing the loss of essential fluids.

2. Microvilli: These small, finger-like extensions on the apical surface of epithelial cells increase the surface area available for absorption or secretion. This adaptation is particularly important in the digestive tract, where microvilli enhance the absorption of nutrients.