How Does Auxin Move in a Plant?

Auxin is a plant hormone that plays a crucial role in growth, development, and responses to environmental stimuli. It moves in a plant through a process called polar transport, which is directional, meaning it moves from one part of the plant to another.

Auxin moves primarily in two ways: through active transport and diffusion. Active transport involves the movement of auxin against a concentration gradient using energy, while diffusion allows it to move along a concentration gradient. Auxin's movement is largely influenced by gravity, light, and plant cell structure.

In the root, auxin accumulates on the lower side, causing cells to elongate and leading to root bending towards gravity. In the shoot, auxin moves towards the shaded side, causing the cells to elongate and bend towards light, a phenomenon known as phototropism.

This ability of auxin to move in specific directions allows plants to grow towards resources like light and water, making it essential for their survival and adaptation.