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Being such a simple soul, my favourite photosynthesis exhibit is the simple 
one where a bright lamp shines onto a short (<100mm) piece of Elodea 
canadensis (called canadian pondweed here in UK) submerged upside-down in 
water. You SEE the light; if neatly displayed you SEE the bright green 
colour of the chlorophyll; and you SEE a procession of tiny silvery bubbles 
of oxygen streaming up from the cut end of the stem. I don't recall seeing 
this done with a close-up video camera and a big screen, but with suitable 
graphics that would look so impressive.

Varying the light intensity changes the distance between the streaming 
oxygen bubbles. But, unfortunately, not quite fast enough to qualify this 
to join my short list of biological interactives with a response time of 
less than 3 seconds: ie. producing a change before the visitor has walked 
away...


[log in to unmask] * http://www.interactives.co.uk
*
Give people facts and you feed their minds for an hour.
Awaken curiosity and they feed their own minds for a lifetime.
*
Ian Russell 

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