Scientists Measured the Pressure in the Xylem of Redwood Trees

question 100

Multiple Choice

Scientists measured the pressure in the xylem of redwood trees at different heights and found that the higher they made their measurements,the lower the pressure.They extrapolated this to a pressure of zero,and concluded that the tallest a tree could grow is 122-130 meters.The tallest know tree on Earth is 112.7 meters.Which of the following most likely limits the height of trees?

• A)the amount of transpiration in leaves
• B)the amount of photosynthesis in leaves
• C)the amount of energy needed to pump water to the tops of the trees
• D)the strength of water cohesion
• E)the ability to take up CO₂

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