What hormone helps plants move toward a stimulus?
A.)Ethylene
<u>B.)Auxins</u>
C.)Acids
Auxin moves to the darker side of the plant, causing the cells there to grow larger than corresponding cells on the lighter side of the plant. This produces a curving of the plant stem tip toward the light, a plant movement known as phototropism. Auxin also plays a role in maintaining apical dominance

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Parietal cells produce the acid