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Where Did the Water Go? The Mystery of a Corn Plant's "Water Intake"
BIOL701A-PEP-CNLesson 7
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Welcome to the "water paradox" of the plant kingdom. Imagine an ordinary corn plant that turns out to be a crazy"super drinker". Over its lifetime, from sprouting to bearing fruit, it draws more than $2000$ kilogramsof water from the soil โ€” equivalent to the weight of $4000$ regular water bottles!

2000kgTotal Water Uptake2.2kgPhysiological UseWater Utilization: ~1%

The "Mysterious Disappearance" of Water

Most astonishingly, of this $2000$ kg of water, only about $2.2$ kilograms(about $1\%$) is actually used to build the plant's body or participate in metabolism. Where did the remaining $99\%$ go? It didn't vanish โ€” instead, it escapes into the atmosphere as invisible water vapor through tiny "windows" on the leaf surface calledstomata. This process is known astranspiration. The plant acts like a giant natural water pump, constantly drawing water from the ground and releasing it into the sky, sustaining the biosphere's water cycle.

Scientific Insight
Why do plants engage in this seemingly "wasteful" behavior? In fact, this upward flow of water provides the driving force for transporting mineral salts and helps "cool" the leaves on hot summer days, preventing them from being scorched by the sun.