Microscale Ocean Biophysics Seminar Series: Anders Andersen (Technical University of Denmark)
Inici: 21/09/2021 17:00 - Fi: 21/09/2021 18:00Lloc: Zoom (Link in the description)
Centre for Ocean Life
National Institute of Aquatic Resources
Technical University of Denmark
Feeding flow and membranelle filtration in ciliates
Ciliates are ubiquitous in the marine environment and important consumers of phytoplankton and flagellates. The feeding in ciliates is complex and relies in many species on coordinated motion in bands of transversal rows of cilia known as membranelles. We explore the feeding in the ciliate Euplotes vannus that uses a single membranelle band to both generate feeding flow, retain food particles, and transport them to the mouth region. To obtain a mechanistic understanding of the feeding, we use high-speed video-microscopy. The cilia move parallel to the membranelle band towards the mouth region in the power strokes, and a metachronal wave propagates away from the mouth region parallel to the band and outwards along the membranelles. From the inside of the band, a gap therefore opens between neighboring membranelles, and while food particles are retained, water is drawn in and pushed across the membranelle band as the gap closes from the inside. We rationalize our findings in a model that compares favorably with our observations of clearance rate and membranelle motion.
This is joint work with Mads Rode and Thomas Kiørboe.