Related Experiment Video
Updated: May 19, 2026
11:41
Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
How the cucumber tendril coils and overwinds
Sharon J Gerbode1, Joshua R Puzey, Andrew G McCormick
1School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|September 1, 2012
Summary
Plant tendrils coil due to asymmetric cell contraction, not unwinding. These specialized structures exhibit unique mechanical properties, acting as twistless springs with tunable responses, inspired by Darwin's observations.
Area of Science:
- Plant biology
- Biomechanics
- Materials science
Background:
- Plant tendril coiling has long fascinated scientists, with Charles Darwin proposing they act as soft springs.
- The precise mechanism of coiling and the mechanical properties of tendrils remain largely unexplored.
Purpose of the Study:
- To elucidate the cellular and mechanical basis of helical tendril coiling.
- To quantify the mechanical behavior of tendrils and compare it to Darwin's hypothesis.
- To explore potential biomimetic applications for twistless springs.
Main Methods:
- Experiments were conducted on cucumber tendrils (Cucumis sativus).
- Mechanical testing involved extracted fiber ribbons and aged tendrils under tension.
- Physical models of prestrained rubber, geometric arguments, and elastic filament models were employed for analysis.
Main Results:
- Tendril coiling is driven by asymmetric contraction of an internal cellular fiber ribbon.
- Under tension, tendrils and fiber ribbons exhibit twistless overwinding, not unwinding.
- A soft initial response transitions to significant strain-stiffening at higher extensions.
Conclusions:
- The study reveals the cellular mechanism behind tendril coiling.
- The mechanical behavior aligns with and quantifies Darwin's soft spring hypothesis.
- Findings suggest designs for novel biomimetic twistless springs with adjustable properties.
Related Concept Videos
01:05Mechanism of Ciliary Motion
The ciliary structures were first seen in 1647 by Antonie Leeuwenhoek while observing the protozoans. In lower organisms, these appendages are responsible for cell movement, while in higher organisms, these appendages help in the movement of the extracellular fluids within the body cavities.
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
01:05Mechanism of Ciliary Motion
The ciliary structures were first seen in 1647 by Antonie Leeuwenhoek while observing the protozoans. In lower organisms, these appendages are responsible for cell movement, while in higher organisms, these appendages help in the movement of the extracellular fluids within the body cavities.
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
02:15The Contractile Ring
Contractile rings are composed of microfilaments and are responsible for separating the daughter cells during cytokinesis. Contractile ring assembly proceeds along with other cell cycle events; however, very few mechanistic details are known about the timing and coordination of the contractile rings with the cell cycle.
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
02:15The Contractile Ring
Contractile rings are composed of microfilaments and are responsible for separating the daughter cells during cytokinesis. Contractile ring assembly proceeds along with other cell cycle events; however, very few mechanistic details are known about the timing and coordination of the contractile rings with the cell cycle.
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
02:57Attachment of Sister Chromatids
As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules. Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...
02:57Attachment of Sister Chromatids
As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules. Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...