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 One step closer to reality
20.04.2018 | Max-Planck-Institut für Entwicklungsbiologie

nachricht The dark side of cichlid fish: from cannibal to caregiver
20.04.2018 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>