If plants close the stomata at night, how can the plants get oxygen? Are all the stom
Posted 7 March 2005 - 09:14 AM
If plants close the stomata at night, how can the plants get oxygen? Are all the stomata fully closed?
If not, the problem is simple because oxygen can still diffuse into the plants in a low rate.
Posted 8 March 2005 - 02:37 AM
My plant physiology is rusty.
Posted 8 March 2005 - 03:35 AM
Posted 8 March 2005 - 03:54 AM
There are some plants, mostly living in desert environments, that follow the CAM pathway. They ONLY open their stomates at night. During that time they take in CO2 and release O2, which is used during the day for photosynthetic processes while the stomates are closed.
Yes, it is inefficient, but it seems to work in places where not much else can grow.
...a postscript of the hope of spring.
Edit: Since when do plants take in Oxegen and release CO2 anyway? Where ARE you getting this info?
Posted 8 March 2005 - 04:29 AM
Edit: Plants take in oxygen and release carbon dioxide like every other living eukaryotic organism, they have mitochondria, perhaps the thing is though they take in water which contains oxygen, then convert this to 6CO2+6H20---> C6H12O6 + 602
But then they release it when they respire, so the equation is balanced, however flucuations in homeostasis would most efficiently be corrected by the diffusion of oxygen from the air.
Posted 8 March 2005 - 05:01 AM
Posted 8 March 2005 - 05:31 AM
Here's a few sites that are spreading the blasphemy.
Most plants use the C3 photosynthetic pathway. Stomates usually only close for these plants during dry periods to conserve water, not at night. In fact, where did you hear that plants close their stoma at night? I believe that is false information.
Posted 8 March 2005 - 05:41 AM
Please, if someone can offer proof that stomates close for any other reason than dehydration or CAM cycling, I would like to see it.
...a postscript to a hope of spring.
Posted 8 March 2005 - 06:22 AM
Similarly stomata predict dusk and start to close many hours before the onset of darkness, reducing water loss.
Webb, Alex A. R. (2003)
The physiology of circadian rhythms in plants.
New Phytologist 160 (2), 281-303.
Posted 8 March 2005 - 01:25 PM
....a postscript to the hope of spring.
Posted 8 March 2005 - 01:43 PM
Edit: The circadian rhythm is largely based on feedback loops of interacting proteins that change in concentration rhythmically. These have effects on various things in the cell that affect the turgor (greater turgor=stomata opening). Ca+ seems to be the most important of these in stomata.
Posted 8 March 2005 - 05:45 PM
This would possibly be similar to the feedback loops that cause flowers to open at certain times of the day. Or maybe not. Pure speculation, until someone gives me evidence.
...a postscript to the hope of spring.
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