Takeaway. If swallowing seems like it’s a complicated function, that’s because it is. In fact, it takes approximately 25 pairs of muscles in the mouth, pharynx, larynx, and esophagus to do this.

Isolated planarian pharynx: two tissue types in this digestive organ are shown. In red, cilia of the epithelial layer ensheathing the organ are labeled with an antibody against acetylated tubulin.

PART 1 Oral cavity, pharynx and esophagus. GI Motility online (2006) doi:10.1038/gimo5 Published 16 May 2006. Anatomy and development of oral cavity and pharynx. Rebecca Z. German, Ph.D. and ...