Which of the following is NOT a part of the mucosa-associated lymphoid tissue (MALT)?

• A. the tonsils
• B. the appendix
• C. the spleen
• D. Peyer's patches

Answer: (C)

Verified step by step guidance

1. Understand the concept of Mucosa-Associated Lymphoid Tissue (MALT): MALT is a collection of lymphoid tissues that protect the mucosal surfaces of the body, such as the gastrointestinal tract, respiratory tract, and urogenital tract.
2. Identify the components of MALT: Common components include the tonsils, the appendix, and Peyer's patches, which are all associated with mucosal surfaces.
3. Recognize the function of the spleen: The spleen is an organ involved in filtering blood and is part of the systemic immune system, not specifically associated with mucosal surfaces.
4. Differentiate between systemic and mucosal immune components: MALT is specifically associated with mucosal immunity, whereas the spleen is part of the systemic immune system.
5. Conclude that the spleen is not part of MALT: Based on its function and location, the spleen does not belong to the mucosa-associated lymphoid tissues.