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Temperature and Transpiration Graphs


Transpiration is the evaporation of water from open stomata in plant leaves. A group of AP Biology students used a potometer to measure transpiration rates in an experiment testing the effect of temperature on the rate of transpiration. They used C3 plants, which do not have any adaptations to prevent photorespiration.

Which of the following graphs shows the experimental results of increased temperature on the rate of transpiration?

Created for Albert.io. Copyright 2016. All rights reserved.


Graph A. Transpiration will increase with increasing temperature up till a maximum rate of water loss and then plateau.


Graph B. Transpiration rates will increase with increasing temperatures exponentially.


Graph C. Increasing temperature will cause a decrease in water loss due to transpiration.


Graph D. Increasing temperature has no effect on the rate of stomata opening and closing in plants.