In article , Franz Heymann
writes

"Kay" wrote in message
...
Aren't there lots of possibilities? Isn't this to do with
crassulacean
acid metabolism (because it was first discovered in the crassulas)
whereby a great many plants in arid regions have adopted a
metabolism
that allows them to do their photosynthesis in effect at night,

Impossible. {:-((

That's what I thought, and why I said 'in effect'.

As I understand it, the stomata of these plants are closed during the
day and open during the night. At night CO2 is taken in and fixed
temporarily using malic acid. The actual photosynthesis, i.e. the use
of the previously absorbed CO2 to form starch (or is it sugar?) still
occurs during the day

I thought it must be a two stage process. Neat idea, anyway. Thanks!
--
Kay
"Do not insult the crocodile until you have crossed the river"