Identify the tissue that forms the lining of very active parts of the body such as the stomach and is a single layer of tall rectangular cells.

• A. Stratified squamous epithelium
• B. Columnar epithelium
• C. Simple cuboidal epithelium
• D. Ciliated epithelium

Answer: (B)

The tissue described is simple columnar epithelium. It forms a single layer of tall, column-shaped cells, which is ideal for lining areas that are very active in secretion and absorption, like the stomach. This arrangement allows specialized cells within the layer to produce mucus and digestive juices while still providing a smooth surface for the passage of contents.

Stratified squamous epithelium is multi-layered and designed for protection in areas of high wear, not for a single, active lining. Simple cuboidal epithelium consists of cube-shaped cells and is more typical of glands and kidney tubules, not tall, columnar cells. Ciliated epithelium has hairlike cilia and is common in the airways, not in the stomach lining. Therefore, columnar epithelium best fits the description.