I heard somewhere that a photosynthetic organism, if left in an 100% oxygen environment, will eventually begin to use cellular respiration (or something like it) and take in oxygen and release CO2...is this true? (didn't want to hijack elf's thread) :)

Question

I heard somewhere that a photosynthetic organism, if left in an 100% oxygen environment, will eventually begin to use cellular respiration (or something like it) and take in oxygen and release CO2...is this true?  (didn't want to hijack elf's thread) :)

anonymous · Answer

dont thinks so the plant would need time to adapt tothat enviroment. and that would not be enough time to adapt before it would suffocate

cathyangs · Answer

oh...thanks TranceNova. I just heard this from my teacher at camp...

anonymous · Answer

If the plant was placed in a 100% oxygen environment (previously exposed to CO2) AND is a C3 plant then during the Calvin Cycle...

02 will eventually bind with the 5-C RuBP molecule eventually will release O2 into the atmosphere. 

However it will not release C02 into atmosphere.

cathyangs · Answer

k. Thanks... but I'm pretty sure we were talking about choloroplasts, mitochondria, and photosynthesis vs. CR

anonymous · Answer

Im not 100% sure on this but photosynthetic plants are autotrophs because they produce and secrete food/fuel for consumers.

If thats the case then CellRes would always be present in photosynthetic organisms. I don't know if organisms can do Photosynthesis without also having the ability to do CellRes

cathyangs · Answer

I'm pretty sure that CR is not with plants...and autotrophs is ecology...not really the biology terms we're using.

trancenova · Answer

It is my understanding that plants do use cellular respiration -its just a matter of source and sink. The chloroplast will produce sugar's which is then used in the plant (sometimes elsewhere in the plant) in respiration to release energy.

cathyangs · Answer

ah...thanks everyone!

trancenova · Answer

Sorry, I'm all sleepy and trying to work this out in my head. In theory if a plant was in an 100% O2 environment it wouldn't survive because it would not be able to photosynthesize, not being able to photosynthesize would mean it would have no sugar income and so wouldn't be able to use sugars for energy. But if the plant had some other supply of sugars the plant would stop photosynthesizing and just respire (like parasitic plants).

anonymous · Answer

plants have to breathe too. of course, the photosynthesis will be slowed down because of the absent CO2, but plants also have a normal metabolism which affords oxygen as power source. so, what will happen, is that your plant will start breathing. as the CO2 tries to get out, it will diffuse into rubisco, being sucked in again. at night, of course, your plant will breathe normally w/o photosynthesis being activated.