membranellelike
Membranellelike is a descriptive term used in cell biology and protistology to refer to cellular structures that resemble membranelles in their appearance or presumed function, but do not meet the strict morphological or developmental criteria of true membranelles. Membranelles themselves are compound ciliary structures forming part of the oral apparatus in many ciliates, typically consisting of densely organized cilia arranged in longitudinal rows that help generate feeding currents. Structures described as membranelle-like may consist of multiple ciliary bands, microtubule-based ribbons, or membranous sheets bearing cilia, oriented in ways that suggest a membranelle origin, yet their ultrastructure, development, or molecular composition differs from canonical membranelles. They may arise as evolutionary variants, developmental intermediates, or secondary adaptations in various protists.
In terms of function, membranelle-like structures are generally implicated in locomotion or feeding, by directing water
See also membranelles; ciliates; oral apparatus; protist ultrastructure.