Practice Questions

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#Question id: 397

The loss of water from a plant by transpiration cools the leaf. Movement of water in transpiration requires both adhesion to the conducting walls and wood fibers of the plant and cohesion of the molecules to each other. A scientist wanted to increase the rate of transpiration of a crop species to extend its range into warmer climates. The scientist substituted a nonpolar solution with an atomic mass similar to that of water for hydrating the plants. What do you expect the scientist's data will indicate from this experiment?

#Unit 1. Molecules and their Interaction Relevant to Biology

The rate of transpiration will be the same for both water and the nonpolar substance.
The rate of transpiration will be slightly lower with the nonpolar substance as the plant will not have evolved with the nonpolar compound.
Transpiration rates will fall to zero as nonpolar compounds do not have the properties necessary for adhesion and cohesion.
Transpiration rates will increase as nonpolar compounds undergo adhesion and cohesion with wood fibers more readily than water.