Breakthrough from Kyoto University
Published on May 31 at 5:10 PM
A team led by Kenta Ishimoto at Kyoto University has discovered that sperm cells violate Newton’s third law of motion due to a property they call 'odd elasticity.' This finding emerged from studying how sperm move through viscous fluids—a challenge long considered difficult and often referred to as the 'scallop theorem.'
How Sperm Move
Sperm function as active systems, continuously generating mechanical energy through their own internal micromotors. They rely on flagella that bend in waves created by molecular engines inside their tails. These traveling waves enable sperm to move efficiently through liquid, counteracting the drag caused by viscosity.
To explain this process in detail, the researchers introduced a new term—'odd elastohydrodynamics'—along with the concept of an 'odd elasticity modulus.' The cell’s internal activity generates traveling waves, while passive elasticity helps stabilize them, leading to more effective motion.
The team’s model was successfully tested against data from human sperm and green algae known as Chlamydomonas. This research opens up new avenues for understanding movement in biological systems and could have significant implications for future studies in biophysics and biomechanics.
This discovery could greatly influence ongoing scientific research in biomechanics and biophysics by offering fresh insights into how living cells move.
Studying active systems like sperm may help develop new technologies that mimic nature’s principles to create more efficient micro- and nanorobots. Additionally, the findings could prove valuable in medicine, particularly for research into infertility and other reproductive health issues.
In a similar vein, research has shown that certain organisms, like the sea cucumber, exhibit remarkable survival mechanisms, thriving even when severed from their main body. This fascinating phenomenon raises questions about resilience in biological systems, much like the sperm cells' unique movement dynamics. To explore how these marine creatures endure in challenging conditions, you can read more about it here.