Question

Where are auxins synthesized? How do they promote phototropism?

Answer 1

Auxins are primarily synthesized in the apical meristem (tip of the stem and roots) and in young leaves. They are then transported to other parts of the plant. Auxins promote phototropism by regulating cell growth in response to light. When a plant is exposed to light, auxins accumulate more on the shaded side of the stem, causing cells on that side to elongate more than those on the illuminated side. This unequal growth results in the bending of the plant toward the light source.