What is the primary role of cilia in the simple columnar epithelium?

• A. To move substances across the epithelial surface
• B. To increase surface area for absorption
• C. To provide structural support
• D. To secrete mucus

Answer: (A)

Verified step by step guidance

1. Understand the structure of simple columnar epithelium: It is a type of epithelial tissue composed of a single layer of tall, closely packed cells. These cells often have microvilli or cilia on their apical surface.
2. Identify the function of cilia: Cilia are hair-like structures that extend from the surface of certain epithelial cells. They are capable of rhythmic movement.
3. Consider the role of cilia in moving substances: Cilia beat in a coordinated manner to move substances, such as mucus or particles, across the epithelial surface.
4. Differentiate between cilia and microvilli: While cilia are involved in movement, microvilli are primarily for increasing surface area to enhance absorption.
5. Evaluate the options: Given the functions of cilia, the primary role in simple columnar epithelium is to move substances across the epithelial surface, distinguishing it from roles like absorption, structural support, or secretion.