Unsteady Motion, Finite Reynolds Numbers, and Wall Effect on Vorticella convallaria Contribute Contraction Force Greater than the Stokes Drag
نویسندگان
چکیده
منابع مشابه
Unsteady motion, finite Reynolds numbers, and wall effect on Vorticella convallaria contribute contraction force greater than the stokes drag.
Contraction of Vorticella convallaria, a sessile ciliated protozoan, is completed within a few milliseconds and results in a retraction of its cell body toward the substratum by coiling its stalk. Previous studies have modeled the cell body as a sphere and assumed a drag force that satisfies Stokes' law. However, the contraction-induced flow of the medium is transient and bounded by the substra...
متن کاملEvaluation of the Mass Transfer Effect of the Stalk Contraction-Relaxation Cycle of <i>Vorticella convallaria</i>
Advisor: Sangjin Ryu Vorticella convallaria is a genus of protozoa living in fresh water. It has a bell-shaped zooid equipped with adoral ciliary bands and a contractile stalk tethering the zooid to a substrate. Vorticella is regarded as a biological spring because its contractile stalk can pull the zooid towards the substrate at a remarkably high speed and then relaxes to its extended state mu...
متن کاملMaximal force characteristics of the Ca(2+)-powered actuator of Vorticella convallaria.
The millisecond stalk contraction of the sessile ciliate Vorticella convallaria is powered by energy from Ca(2+) binding to generate contractile forces of ∼10 nN. Its contractile organelle, the spasmoneme, generates higher contractile force under increased stall resistances. By applying viscous drag force to contracting V. convallaria in a microfluidic channel, we observed that the mechanical f...
متن کاملPower-limited contraction dynamics of Vorticella convallaria: an ultrafast biological spring.
Vorticella convallaria is one of the fastest and most powerful cellular machines. The cell body is attached to a substrate by a slender stalk containing a polymeric structure-the spasmoneme. Helical coiling of the stalk results from rapid contraction of the spasmoneme, an event mediated by calcium binding to a negatively charged polymeric backbone. We use high speed imaging to measure the contr...
متن کاملMaximal Force Characteristics of the Ca[superscript 2+]- Powered Actuator of Vorticella convallaria
The millisecond stalk contraction of the sessile ciliate Vorticella convallaria is powered by energy from Ca2þ binding to generate contractile forces of ~10 nN. Its contractile organelle, the spasmoneme, generates higher contractile force under increased stall resistances. By applying viscous drag force to contracting V. convallaria in a microfluidic channel, we observed that the mechanical for...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Biophysical Journal
سال: 2010
ISSN: 0006-3495
DOI: 10.1016/j.bpj.2010.02.025