raphe

(noun)

a ridge or seam on an organ, bodily tissue, or other structure, especially at the join between two halves or sections

Examples of raphe in the following topics:

Chromalveolata: Stramenopiles
- Some diatoms exhibit a slit in their silica shell called a raphe.
- By expelling a stream of mucopolysaccharides from the raphe, the diatom can attach to surfaces or propel itself in one direction.