00:01
Where does the oxygen produce during photosynthesis come from? co2, carbohydrates, nadph and atp, the air the plant takes in, or water.
00:15
So i'll start by putting the formula for photosynthesis.
00:19
So photosynthesis is all about building up simple sugars.
00:23
So the raw materials we need are co2, h2 and sunlight, and out of that, we get glucose and we get oxygen.
00:36
So these are the inputs for photosynthesis, and these are the outputs.
00:41
And the oxygen, the output, is a side product.
00:45
So from this, we can say, well, the oxygen can only possibly come from one of the inputs.
00:52
It has to come from somewhere, and it's not coming from the carbohydrates, because that's the product.
00:58
It's not coming from nadph or atp because those are recycled as part of this.
01:07
They're not lost, so the oxygen can't be coming from them.
01:11
And it's not from the air the plant takes in, because that doesn't feature in this equation, apart from the co2.
01:18
So it has to be the co2 of water.
01:20
And both of them have oxygen in them.
01:22
So which one does it actually come from? well, it comes from the water.
01:27
So photosynthesis has two types of reaction.
01:32
The light and the dark, or the light dependent and the light independent.
01:36
The light independent, the dark reactions have the calvin cycle.
01:41
And the calvin cycle fixes co2.
01:45
So it takes in carbon dioxide and it builds organic molecules out of it and gives you glucose.
01:51
But to do this, it requires energy and it requires reducing power...