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Updated: Jun 26, 2025
10:07
Measuring Sperm Guidance and Motility within the Caenorhabditis elegans Hermaphrodite Reproductive Tract
Published on: June 6, 2019
12.3K
Hybrid motility mechanism of sperm at viscoelastic-solid interface
Shobitha Unnikrishnan1, Robert Scott1, Emmanuel Ogundele1
1North Carolina Agricultural and Technical State University.
Research Square
|May 15, 2024
Summary
Sperm motility involves more than just swimming. Direct interaction between the sperm tail (flagellum) and surfaces generates thrust, aiding efficient movement through the female reproductive tract.
Area of Science:
- Reproductive Biology
- Biophysics
- Fluid Dynamics
Background:
- Sperm must navigate complex female reproductive tracts to fertilize eggs.
- Sperm motility was traditionally attributed solely to interaction with surrounding fluids.
- The role of surface topography in sperm guidance is known, but direct surface interaction in motility was unexplored.
Approach:
- Investigated sperm movement in viscoelastic fluids using microfluidic devices.
- Visualized flagellar interaction with surfaces at the microscale.
- Analyzed fluid flow fields generated by sperm to understand boundary conditions.
Key Points:
- Sperm flagella remain close to surfaces during movement.
- Kinetic friction between the flagellum and surface provides propulsive thrust.
- Observed fluid slip at the surface, challenging the standard no-slip boundary condition.
Conclusions:
- Sperm exhibit a hybrid motility mechanism, combining fluid propulsion with direct flagellum-surface interaction.
- This surface-assisted motility is a key evolutionary adaptation for sperm migration in narrow, mucus-filled reproductive tracts.
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