Assuming these are carbon dioxide molecules, which way do you think the molecules will move and why? A. Out of the cell. They want to move from high to low concentration (DOWN the concentration gradient)

B. Into the cell. They want to move from low to high concentration (UP the concentration gradient).

A. Out of the cell. They want to move from high to low concentration (DOWN the concentration gradient)

Explanation:

Although the cuticle provides important protection from excessive water loss, leaves cannot be impervious because they must also allow carbon dioxide in (to be used in photosynthesis), and oxygen out. These gases move into and out of the leaf through openings on the underside called stomata (Figure 3b).