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Bionics — Ingenious
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Phenomena of Nature
"I'm sitting on the uppermost floor of a high-
rise building. The wind is blowing relent-
lessly and makes the skyscraper rock omi-
nously back and forth. At some point,
it happens: The tip of the skyscraper
bends down so low that it even touch-
es the ground. 'Now it's surely going
to break,' I think. But the thought
has hardly passed when the high-rise
stands up again and the incessant
back-and-forth continues. But thank
goodness — the building is holding to-
gether." This is how a lonely ant might
sound when reporting about the experi-
ences it has as it holds tightly onto the tip
of a blade of grass in a gusty windstorm.
So how does a 50 centimeter-tall blade of grass
measuring only one centimeter thick manage not to
be blown over by the gentlest of breezes? How do the leaves
of a lotus plant clean themselves? More and more engineers
are interested in these and other similar questions as they try
to adapt ingenious systems found in nature for use in engi-
neering and technology.
Blades of Grass and Roots — Botanical Architecture
Every skyscraper architect is faced with complicated problems. They must ensure
that their skyscraper doesn't simply break in half under strong wind, for example.
Nature also faces the same problems when it decides to build upward — and it has
found some incredible solutions.
Grass Blades — Rigid, Light Design
The blade of grass on which the ant is sitting has to be both stable and flexible at
the same time. Sufficient flexibility is already ensured by the construction material
alone. Plant cells can be compressed and stretched to a limited extent. But what
stabilizes a grass blade?
Plants have invented certain cell types whose task it is to ensure stability. Botanists
call it support tissue. You can imagine that especially stabile cells must also look
stable. The most striking feature of these cells is that they have particularly thick
cell walls. But that's not all. A special cement called lignin is also lodged in the cell
walls which makes the cell wall even more rigid. Lignin is a wood-like substance
which is found in great quantities, of course, in tree trunks. Tree trunks and even
bark are made up almost exclusively of this cement tissue. Water ducts that travel
upward through a plant stem have two tasks: They conduct the water through the
plant and provide stability with their thick cell walls.
Grasses are built to be rigid in order to withstand
the wind.
Even transmitter towers and television towers fol-
low the constructional principle found in grasses.
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