Experiment: If you tie a plastic bag over a leaf and place the plant in light, you will be able to see water condensing inside the plastic bag. The water is let out by the leaves.
The leaves have tiny, microscopic holes called stomata. Water evaporates through these stomata. Each stomata is surrounded by guard cells. These guard cells help in regulating the rate of transpiration by opening and closing of stomata.
Typically, only 0.1 percent of water taken up by the plant is used by the plant for producing carbohydrates. That is, if a plant absorbs one litre of water, only one millilitre will be used to produce carbohydrate. The remaining 999 millilitres evaporates from the leaf.
You will be able to see how much water a plant releases in the air.
