Which of the following structures serve to increase the surface area of a cell for absorption and secretion?

• A. Centrioles
• B. Cilia
• C. Flagella
• D. Microvilli

Answer: (D)

Verified step by step guidance

1. Understand the function of microvilli: Microvilli are small, finger-like projections on the surface of certain cells, particularly epithelial cells. Their primary role is to increase the surface area of the cell, enhancing its ability to absorb nutrients and secrete substances.
2. Compare microvilli to other structures: Centrioles are involved in cell division and do not contribute to surface area. Cilia are hair-like structures that move substances across the cell surface, and flagella are tail-like structures used for cell movement. Neither cilia nor flagella are specialized for increasing surface area.
3. Relate structure to function: The increased surface area provided by microvilli is crucial for cells in areas like the intestines, where absorption of nutrients is vital. This structural adaptation allows for more efficient interaction with the environment.
4. Visualize the concept: Imagine microvilli as tiny extensions of the cell membrane, similar to how folds in a fabric increase the amount of material in a given space. This analogy helps understand how microvilli maximize surface area.
5. Conclude the reasoning: Based on the comparison and understanding of functions, microvilli are the correct answer because they are specifically designed to increase the surface area for absorption and secretion.