The sea urchins tough, brittle spines are an engineering wonder. Composed of a single crystal from base to needle-sharp tip, they grow back within a few days after being broken off. Now, a team of scientists at the Weizmann Institute of Science has shown how they do it.
While many crystals grow from component atoms or molecules that are dissolved in liquid, sugar and salt being the most familiar examples, the team of Profs. Lia Addadi and Steve Weiner, of the Institutes Structural Biology Department, found that the sea urchin uses another strategy. The material of the spines is first amassed in a non-crystalline form, termed "amorphous calcium carbonate" (ACC). Packets of ACC are shoveled out of the cells surrounding the base of the broken spine and up to the growing end. Within hours of arriving in place, the amorphous material, which is composed of densely packed, but disorganized molecules, turns to calcite crystal in which the molecules line up evenly in lattice formations.
Working with graduate student Yael Politi and Eugenia Klein and Talmon Arad of the Chemical Research Support Unit, Professors Addadi and Weiner used four different methods of investigation, including two kinds of electron microscopy, to look for the ACC as it was being deposited and turning to crystal. "The question," says Weiner "is why it should be so difficult to observe a process that seems to be so basic. Scientists have been studying it for over a hundred years. In fact, because the ACC is a transient phase, we had to develop new methods to catch it while it exists."
Jeffrey J. Sussman | EurekAlert!
More genes are active in high-performance maize
19.01.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn
How plants see light
19.01.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
19.01.2018 | Materials Sciences
19.01.2018 | Health and Medicine
19.01.2018 | Physics and Astronomy