EM 292 Appendix

Appendix

Scanning electron micrograph (SEM) of the appendix in the large intestine.

The appendix is a tubular evagination in the cecum of the large intestine. The lumen of the appendix is usually small and frequently contains dead cells and detritus.

Large rounded projections (yellow) are apparent in the folded mucosa (blue). These projections are folds of the epithelial layer over lymphatic nodules, which occur in large numbers in the underlying lamina propria and submucosa.

The smaller apertures (black) in the folded mucosa are openings into intestinal glands (or crypts of Lieberkuhn).