Following allergen inhalation, reduction in exhalation capacity of more than 20 percent, and for at least 10 to 20 minutes, indicates a positive reaction to the allergen and the sensitivity of the individual being tested.
One of the constant features of respirationthe exhalation of carbon dioxide can still be observed.
The entry of gases into, and exit from, the cells, as well as the actual exhalation of watery vapour from the latter, take place in the intercellular space system of which the stomata are the outlets.
If this exhalation is stopped or lessened the digestion in its turn is also stopped, the leaf remains longer than usual in the intestines, the microbes multiply, invading the whole body, and this brings about the sudden death which surprises the rearers.
Baldwin Latham made an elaborate examination of the meteorological conditions, and more particularly of the vapour tension, from which he draws the conclusion that the seasonal variations are due to exhalation from the ground.