Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Harvard scientists discover how the venus flytrap snaps

27.01.2005


A team of applied mathematicians, physicists, and biologists has discovered how the Venus flytrap snaps up its prey in a mere tenth of a second by actively shifting the curved shape of its mouth-like leaves. Their study, published in the Jan. 27 issue of the journal Nature, investigates the series of events that occur from the time the plant’s leaves are stimulated to the time the trap is clamped shut.


Superposition of the open and closed leaves of the Venus flytrap. The glass needle in the foreground was used to trigger the closure. Note that the leaves flip by almost turning inside out - similar to the flipping of a contact lens, plastic lid or the reversal of a torn tennis ball. Courtesy of Forterre and Mahadevan.



"Our work complements prior research," says Lakshminarayanan Mahadevan, Gordon McKay Professor of Applied Mathematics and Mechanics in Harvard University’s Division of Engineering and Applied Sciences and affiliate in the Department of Organismic and Evolutionary Biology in Harvard’s Faculty of Arts and Sciences. "In addition to looking at biochemical events, we looked at what happened after the plant was stimulated and found that the rapid closing is due to a ’snap-buckling instability’ that the plant itself controls."

To trap its prey, the carnivorous plant relies on both an active biochemical and a passive elastic process, say Mahadevan and former students and postdocs Yoël Forterre, Jan M. Skotheim, and Jacques Dumais. When an insect brushes up against a hair trigger, the plant responds by moving water to actively change the curvature of its leaves. While exactly how the water is moved is not completely understood, the scientists observed that the deformation of the leaves, once stimulated, provided the means by which elastic energy was stored and released, creating a simple yet effective jaw-like movement.


"In essence, a leaf stretches until reaching a point of instability where it can no longer maintain the strain," Mahadevan says. "Like releasing a reversed plastic lid or part of a cut tennis ball, each leaf folds back in on itself, and in the process of returning to its original shape, ensnares the victim in the middle. The hydrated nature of the leaf quickly dampens the vibrations caused by the movement, so the unlucky bug doesn’t spill out. It then takes the plant up to eight hours to ready its leaves for the next unsuspecting bug."

To reveal how the Venus flytrap snaps, the researchers painted ultraviolet fluorescent dots on the external face of the leaves and filmed them under ultraviolet light using high-speed video. By using mirrors to record stereo images of the process, they were able to reconstruct the geometry of the leaf. Finally, a simple mathematical model provided them with a way to understand the quantitative and qualitative aspects of snapping such as when the plant snaps, how long it takes before it goes into action once stimulated, and how fast the entire process happens.

"Our explanation relied on interplay between theory and experiment, and on the interdisciplinary interests and nature of our group, with expertise ranging from applied math and physics to biology," Mahadevan says.

In addition to shedding light on an age-old riddle involving a plant Charles Darwin called "one of the most wonderful in the world," the discovery has implications for biomimetic systems. One day, engineers might be able to emulate the plant’s ingenious alternative to muscle-powered movements in tiny artificial devices, such as those that control the flow of minute amounts of liquids or gases. Common applications that already use related technology include valves and switches in microfluidic devices, hydraulic sensors and actuators and timed-release drug delivery mechanisms.

Prior explanations of Venus flytrap operation have cited a loosening of cell walls combined with a quick loss of cellular pressure, but it had not been clear how these cellular mechanisms alone could produce the lightning-fast closure of the entire leaf.

Steve Bradt | EurekAlert!
Further information:
http://www.harvard.edu
http://www.deas.harvard.edu/research/Venusflytrap.html.

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>