Which of the Following Has the Lowest (Most Negative)water Potential

Question

Which of the following has the lowest (most negative)water potential?
A) root cortical cells
B) root xylem
C) trunk xylem
D) leaf cell walls
E) leaf air spaces

Accepted Answer

Leaf air spaces have the lowest (most negative) water potential because water potential is lowest in areas where water is most likely to evaporate into the air, such as the air spaces in leaves. This drives the movement of water from the roots through the plant to the leaves.