Raphe

Definition

A raphe is a longitudinal groove found on the surface of certain protists, especially diatoms. It plays a critical role in their locomotion and attachment to surfaces.

5 Must Know Facts For Your Next Test

1. The raphe is essential for the gliding movement observed in some diatoms.
2. It is typically found on pennate diatoms.
3. The structure allows these organisms to secrete mucilage for attachment and movement.
4. Raphes are often paired, running along both sides of the frustule (shell) of the diatom.
5. This feature distinguishes pennate diatoms from centric diatoms, which do not have a raphe.

Review Questions

Related terms

Diatom: Single-celled algae with silica cell walls, important as primary producers in aquatic ecosystems.

Frustule: The silica-based outer shell or cell wall of a diatom.

Mucilage: A gel-like substance secreted by some organisms, used for attachment and protection.