LARGE INTESTINE
BODY OF STOMACH
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the presence of transitional epithelium in the mucous membrane
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the presence of a large accumulation of lymphoid tissue
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many crypts and villi
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lack of muscle
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Detailed explanation-1: -The mucosa of the appendix is colonic in type. However, the most prominent feature is the abundance of lymphoid tissue that lies within both the lamina propria and submucosa (Fig. 1-15). The lymphoid tissue is particularly prominent in younger individuals, and dissipates gradually over the person’s lifetime.
Detailed explanation-2: -First, it is a concentrate of lymphoid tissue resembling Peyer’s patches and is the primary site for immunoglobulin A production which is crucial to regulate the density and quality of the intestinal flora. Second, given its shape and position, the Appendix could be a unique niche for commensal bacteria in the body.
Detailed explanation-3: -The appendix is the only known human lymphoid tissue with B cells expressing IL-6R endogenously unlike the spleen, tonsils or peripheral blood mononuclear cells (PBMC) which only express IL-6R when stimulated by a mitogen.
Detailed explanation-4: -The most characteristic property of the appendix is the presence of masses of lymphoid tissue in the mucosa and submucosa.