That stupid liberal arts education was worthless.
I know photosynthesis is a little complicated, but what’s the deal here?
Yes, plants emit carbon dioxide (respire)at night.
During the day, they get the energy they need for fixing carbon dioxide as well as other metabolic processes via the photosynthetic reactions of the chloroplast. At night the energy the plant needs to maintain itself is derived from the breakdown of sugars in the mitochondria.
Obviously, in order to sustain growth, plants take in more CO2 in the daytime than they release at night. So the net result is that plants are a “CO2 sink”.
I know it’s a bit like a piece of string, but how much oxygen (or carbon dioxide at night) do plants emit?
Say I have a six foot tall lemon tree with a couple of hundred leaves. Are we talking a litre of oxygen a day?
Maybe it’s better to work on areas - what would an acre (or hectare) of medium density forest produce?
And if I was locked in an 8m3 vault, how many pot plants would I need to keep me alive?
Depends how many of them you smoke, dude. And you’d also need a source of light, for the plants to photosynthesize; and some food, and water, and a cable modem, and…say, how long were you planning to stay in the vault for, anyway? Not my idea of a vacation destination.
Not those kinds of pot plants!
Marcus - Someone did an experiment with that. They got this one guy in an airtight room with what looked like about half an acre of corn. He had to exercise regularily just to produce enough carbon dioxide for the plants. Squink, its a common misconception that plants do not respire during the day. They do. They respire the whole time, like us. From the experiment above, it seems that plants cannot survive on their own (I.e. they produce more oxygen than carbon dioxide)
I can remember that hospitals used to remove plants from rooms at night because it was thought that they removed oxygen (or, possibly, emitted carbon dioxide) at night.
They no longer do this so someone must have ‘wised’ up.
That depends on what you mean by respiration. If you are only concerned with whether the plants organelles carry out reactions which release CO2, then yes, plants respire during the day. If instead you look at the whole plant, you’ll find that rather than releasing CO2 during the day, plants take it up and release oxygen instead. At night, plants will continue to take up CO2 until they run out of the (photosynthetically derived) energy to do so, after which they end up absorbing O2 and putting out CO2 to the atmosphere, as they oxidize sugars to maintain metabolism.