oxygen bubbles from photosynthesis

[Ross Koning]

At 1:56 PM -0400 5/27/97, nb2 wrote:
>        In our freshman nonmajors course we measure photosynthesis by timing
>the rise of vacuum-infiltrated spinach leaf disks on oxygen bubbles
>generated in the light.  Spinach from the supermarket works slowly, spinach
>we grow in the greenhouse works much faster, but we can only grow it in the
>fall because of bolting.  Does anyone know of another species that works as
>well as spinach?
>                                                Neal Barnett

Neal,

I routinely use Dieffenbachia leaves from our greenhouse
and they work VERY well.  The cultivar I use has most of
the blade white with a dark green border (I got it at the
grocery store one year, so I don't know it's cv name, sorry).
The advantage is that the discs sink well, rise rapidly,
and you can do a comparison between discs from the white
area vs discs from the green area.  I assume that you
are doing the project with a bicarbonate buffer?  That is
ESSENTIAL to rapid responses.

ross

_______________________________________________________________
Ross Koning                 | koning at ecsu.ctstateu.edu
Biology Department          | http://koning.ecsu.ctstateu.edu/
Eastern CT State University | phone: 860-465-5327
Willimantic, CT 06226 USA   | fax: 860-465-4479
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