American Academy of Professional Coders (AAPC) Practice Exam

Which type of membrane is involved in absorption and secretion?

1. Mucous Membrane

2. Serous Membrane

3. Synovial Membrane

4. Meninges

The correct answer is: Mucous Membrane

The mucous membrane is primarily responsible for absorption and secretion. It lines various parts of the body, including the respiratory, digestive, and urogenital tracts, where it serves crucial functions in facilitating the intake of nutrients and the release of waste or other substances. The secretions produced by mucous membranes, which often contain mucus, help to lubricate and protect the underlying tissues, enabling effective absorption in the digestive tract and providing a barrier against pathogens. Other membrane types mentioned serve different functions. Serous membranes are thin layers that produce serous fluid to reduce friction between organs, particularly in body cavities like the thorax and abdomen. Synovial membranes line the cavities of joints and produce synovial fluid that lubricates and nourishes the cartilage surfaces. Meninges are protective layers covering the brain and spinal cord, providing support and protection rather than involvement in absorption or secretion. Thus, the unique role of the mucous membrane in absorption and secretion makes it the correct answer.