Which structure anchors epithelia to underlying connective tissue?

• A. Lamina propria
• B. The basement membrane
• C. Alveolar epithelium
• D. Goblet cells

Answer: (B)

Anchoring epithelial sheets to the connective tissue beneath them is achieved by a specialized extracellular matrix called the basement membrane. This thin layer sits at the base of the epithelium and is formed in part by epithelial cells (basal lamina) and in part by the underlying connective tissue (reticular lamina). It provides a stable attachment through cell–matrix connections like hemidesmosomes and also acts as a selective barrier and signaling scaffold. The lamina propria is the connective tissue beneath mucosal epithelia, not the anchoring structure itself; alveolar epithelium refers to a type of epithelium in the lungs, and goblet cells are mucus-secreting cells within epithelia. Therefore, the basement membrane is the structure that anchors epithelia to underlying connective tissue.