video 1

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in fact there exists a highly efficient
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motor with energy conversion efficiency
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of virtually 100% what is more it
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rotates at a maximum speed of 1500
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revolutions per second far faster than
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even a fastest Formula One racecar
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engine a bacterial flagler motor with a
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diameter of only 40 nanometers it is
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composed of protein molecules 2
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micrometer sized bacteria rotate its
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flagella of 10 to 15 micrometers in
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length to achieve motility bacterial
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flagella are composed of about 30
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different proteins first a protein
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called
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fly F forms a rotor ring in a cell
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membrane fly F self-assembles to form
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the ring which then becomes the
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foundation for other proteins to attach
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which in turn becomes the foundation for
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the attachment of others the
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self-assembly takes place in methodical
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order through the accurate recognition
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of appropriate others with a motor in
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place as the foundation the filament
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that acts as the propeller is then
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formed of proteins called flagellum with
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the help of a capping protein at the tip
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flatulent molecules sent out from the
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cell body through the central channel of
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the motor step up to form a helical
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tubular structure
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this structure reviewed by electron
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microscopy was very much like an
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artificial motor with its stator rotor
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and bushing and surprised the world
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image analysis of electron micrographs
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of straight flagella filaments led to a
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three-dimensional image near atomic
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level the central channel of the
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filament was extremely small only 2
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nanometers in diameter
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self-assembly of the flagellum which
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grows out of the cell always occurs at
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its distal growing end the component
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proteins are produced inside of the cell
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and sent out to the tip through the
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central channel
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the proteins are unfolded for insertion
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into the channel and then refolded at
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the distal end where then is the export
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apparatus research on platter protein
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export had been progressing extremely
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slowly until recently all of these
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experiments have shown that flagler
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protein export occurs in the following
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manner first fly I associates with to
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fly H molecules a flagel ER protein to
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be exported also binds to them and this
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ternary protein complex binds to the C
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ring and waits for the export gate to
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become disengaged when the export gate
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is free and available the ternary
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protein complex docks to the export gate
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together with free fly h high complexes
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that are floating nearby or attaching to
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the C ring the gate is closed when it is
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free however it opens when the fly h:i
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hexamer ring complex binds to it and
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efficiently inserts the amino terminus
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of the flagella protein into the gate
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later fly H and fly I detach from the
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export gate through ATP hydrolysis the
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export gate utilizes proton motive force
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to send flagella proteins into the
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channel it unfolds flagella proteins
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into long stretched chains for export
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into the 2 nanometer channel
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once the whole chain is within the
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channel it is transported to the distal
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end of the flagellum meanwhile the fly H
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I complex –is that have detached from
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the export gate bind another flagyl
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approaching and bring it to the waiting
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circle on a searing repeating the cycle
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of binding and release for efficient
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export the flageolet proteins exported
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in this way bind one after another to
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the distal end the flagellum becomes
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longer and it eventually becomes
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possible for the bacteria to swim the
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rotation of the motor is transmitted to
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the flageolet filament with a gentle
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helical structure to generate propulsion
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the hook acts as a universal joint so
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that the torque can be transmitted
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regardless of the orientation of the
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flagella filament bacteria can swim
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about freely because of this what is the
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mechanism here
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the structure of the hook was studied in
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detail to learn the secret the hook is a
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tube of fifty five nanometers in length
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in which roughly 130 hook protein
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subunits are bonded together this is the
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atomic model of the hook the d2 domains
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of the hook protein are strongly bonded
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to one another on the hook surface to
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form the right-handed six stranded helix
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is much like a spring and they form a
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kind of mesh structure with the d1
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domains on the inside this is what
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brings about the rigidity against
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torsion
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joined while there is a large variation
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in the length of the flagellar filament
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the length of the hook is almost
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constant at 55 nanometers
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mutants with hooks longer or shorter
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than 55 nanometers cannot swim properly
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so how then do hooks have the
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predetermined length of 55 nanometers
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the mechanism that determines hook
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length is as follows first what protein
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molecules are efficiently exported and
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the hook becomes nearly fifty five
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nanometers in length
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the autocatalytic cleavage of flu beam
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slows down the export of hook protein
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then several fly key molecules are
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exported to measure hook length
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in other words the cleavage of Looby
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works as a molecular timer that controls
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the speed of hook protein export as you
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can see the precision mechanisms for
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constructing biological nano structures
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are becoming clarified

video 2

video 3

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in Darwin’s black box in 1996 Behe
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spotlighted and made famous a number of
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really interesting discoveries that had
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been occurring in biochemistry and cell
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biology over the last two or three
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decades and what what biologists
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molecular biologists cell biologists
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microbiologist have been discovering is
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that at the level of individual cells
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there are little tiny examples of
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nanotechnology little tiny machines at
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work the flagellar motor is the one that
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be he made most famous it’s a rotary
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engine that powers a whip-like tail
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protein tail that functions like a
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propeller and it moves the bacterium
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through liquid enabling the bacterium to
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essentially track down its food its food
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supply and this little machine includes
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a rotor a stator a driveshaft a u-joint
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bushings bearings and a whip-like tail
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that functions like a propeller and the
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machine and some in some bacterial
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systems turns at a hundred thousand rpms
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in one direction and can reverse
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direction on a quarter of a turn and
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turn a hundred thousand rpm in the other
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direction and bacterial flagellum is a
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true nanomachine of 40 nanometers in
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size it’s amazing I mean e coli
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Salmonella which are kind of our model
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systems for the bacterial flagellum can
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propel a cell about 20 lengths per
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second through a very viscous medium
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like water to these organisms and you
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extrapolate that to human scale funny
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body lengths per second six-foot person
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you know times 20 120 120 feet per
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second Mark Spitz or Phelps would be
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setting records with this type of
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propulsion it’s hardwired into a signal
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transduction ‘el transduction circuit
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that allows the bacterium to sense
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changes in the sugar gradient in the in
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the surrounding liquid this signal
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transduction system is actually a
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short-term memory system where the cell
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is if it’s going in the direction of an
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attractant a nutrient that it can use
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to metabolize it follows that chemical
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gradient if it’s a repellant it will
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sense that and move in in the opposite
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direction so it’s more than just this
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engine it’s an extraordinary piece of
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nanotechnology it’s high-tech in low
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life and so just by spotlighting these
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extraordinary pieces of nanotechnology
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inside cells and the flagellar motor
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wasn’t the only one won by any means be
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he in a sense opened up a window for
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people he opened up the black box of the
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of the inner workings of the cell and
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said look this is a much more
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complicated anything that then than
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anything that the early evolutionary
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biologists had envisioned Darwin knew
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nothing of this type of nanotechnology
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in cells and at the very least we’ve got
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to come up with an explanation for this